Highly enantio- and diastereoselective organocatalytic domino michael-aldol reactions of β-diketone and β-ketosulfone nucleophiles with α,β-unsaturated ketones

Advanced Synthesis and Catalysis

Volumn 346, Issue 9-10, 2004, Pages 1077-1080

  Pulkkinen, Juha ^a   Aburel, Pompiliu S ^a   Halland, Nis ^a   Jørgensen, Karl Anker ^a  

^a AARHUS UNIVERSITY   (Denmark)

Author keywords

Asymmetric catalysis; C C bond formation; Cyclization; Cyclohexanone; Domino reactions; Michael aldol; Organic catalysis

Indexed keywords

CYCLOHEXANONE DERIVATIVE; DIKETONE; IMIDAZOLINE; KETONE DERIVATIVE; SULFONE DERIVATIVE;

ALDOL REACTION; ARTICLE; CATALYSIS; CHEMICAL ANALYSIS; CHEMICAL STRUCTURE; CHIRALITY; ENANTIOSELECTIVITY; MICHAEL ADDITION; ORGANIC CHEMISTRY; STEREOCHEMISTRY; STRUCTURE ANALYSIS; SYNTHESIS;

EID: 5444266167     PISSN: 16154150     EISSN: None     Source Type: Journal    
DOI: 10.1002/adsc.200404115     Document Type: Article

References (42)

1. a) Comprehensive Asymmetric Catalysis, Vols. I-III, (Eds.: E. N. Jacobsen, A. Pfaltz, H. Yamamoto), Springer: Berlin, 1999;
2. b) Catalytic Asymmetric Synthesis, 2nd edn., (Ed.: I. Ojima), Wiley: Chicester, 2000.
3. For recent reviews on asymmetric organocatalysis, see: a) P. I. Dalko, L. Moisan, Angew. Chem. Int. Ed. 2001, 40, 3726; b) H. Gröger, J. Wilken, Angew. Chem. Int. Ed. 2001, 40, 529; c) B. List, Tetrahedron 2002, 55, 5573; d) E. R. Jarvo, S. J. Miller, Tetrahedron 2002, 58, 2481.
4. For recent reviews on asymmetric organocatalysis, see: a) P. I. Dalko, L. Moisan, Angew. Chem. Int. Ed. 2001, 40, 3726; b) H. Gröger, J. Wilken, Angew. Chem. Int. Ed. 2001, 40, 529; c) B. List, Tetrahedron 2002, 55, 5573; d) E. R. Jarvo, S. J. Miller, Tetrahedron 2002, 58, 2481.
5. For recent reviews on asymmetric organocatalysis, see: a) P. I. Dalko, L. Moisan, Angew. Chem. Int. Ed. 2001, 40, 3726; b) H. Gröger, J. Wilken, Angew. Chem. Int. Ed. 2001, 40, 529; c) B. List, Tetrahedron 2002, 55, 5573; d) E. R. Jarvo, S. J. Miller, Tetrahedron 2002, 58, 2481.
6. For recent reviews on asymmetric organocatalysis, see: a) P. I. Dalko, L. Moisan, Angew. Chem. Int. Ed. 2001, 40, 3726; b) H. Gröger, J. Wilken, Angew. Chem. Int. Ed. 2001, 40, 529; c) B. List, Tetrahedron 2002, 55, 5573; d) E. R. Jarvo, S. J. Miller, Tetrahedron 2002, 58, 2481.
7. For the seminal work on the related Robinson annulation see; a) U. Eder, G. Sauer, R. Wiechert, Angew. Chem. Int. Ed. 1971, 10, 496; b) Z. G. Hajos, D. R. Parrish, J. Org. Chem. 1974, 39, 1615; for an example of another organocatalytic asymmetric domino reaction, see: c) D. B. Ramachary, N. S. Chowdari, C. F. Barbas III, Angew. Chem. Int. Ed. 2003, 42, 4233; for another example of an organocatalytic Michael-aldol reaction see; d) F. Tanaka, R. Thayumanavan, C. F. Barbas III, J. Am. Chem. Soc. 2002, 124, 8523.
8. For the seminal work on the related Robinson annulation see; a) U. Eder, G. Sauer, R. Wiechert, Angew. Chem. Int. Ed. 1971, 10, 496; b) Z. G. Hajos, D. R. Parrish, J. Org. Chem. 1974, 39, 1615; for an example of another organocatalytic asymmetric domino reaction, see: c) D. B. Ramachary, N. S. Chowdari, C. F. Barbas III, Angew. Chem. Int. Ed. 2003, 42, 4233; for another example of an organocatalytic Michael-aldol reaction see; d) F. Tanaka, R. Thayumanavan, C. F. Barbas III, J. Am. Chem. Soc. 2002, 124, 8523.
9. For the seminal work on the related Robinson annulation see; a) U. Eder, G. Sauer, R. Wiechert, Angew. Chem. Int. Ed. 1971, 10, 496; b) Z. G. Hajos, D. R. Parrish, J. Org. Chem. 1974, 39, 1615; for an example of another organocatalytic asymmetric domino reaction, see: c) D. B. Ramachary, N. S. Chowdari, C. F. Barbas III, Angew. Chem. Int. Ed. 2003, 42, 4233; for another example of an organocatalytic Michael-aldol reaction see; d) F. Tanaka, R. Thayumanavan, C. F. Barbas III, J. Am. Chem. Soc. 2002, 124, 8523.
10. For the seminal work on the related Robinson annulation see; a) U. Eder, G. Sauer, R. Wiechert, Angew. Chem. Int. Ed. 1971, 10, 496; b) Z. G. Hajos, D. R. Parrish, J. Org. Chem. 1974, 39, 1615; for an example of another organocatalytic asymmetric domino reaction, see: c) D. B. Ramachary, N. S. Chowdari, C. F. Barbas III, Angew. Chem. Int. Ed. 2003, 42, 4233; for another example of an organocatalytic Michael-aldol reaction see; d) F. Tanaka, R. Thayumanavan, C. F. Barbas III, J. Am. Chem. Soc. 2002, 124, 8523.
11. For examples of organocatalytic asymmetric conjugate addition reactions, see: a) M. Yamaguchi, T. Shiraishi, M. Hirama, Angew. Chem. Int. Ed. 1993, 32, 1176; b) A. Kawara, Taguchi, Tetrahedron Lett. 1994, 35, 8805; c) M. Yamaguchi, T. Shiraishi, M. Hirama, J. Org. Chem. 1996, 61, 3520; d) M. Yamaguchi, Y. Igarashi, R. S. Reddy, T. Shiraishi, M. Hirama, Tetrahedron 1997, 53, 11223; e) M. Yamaguchi, T. Shiraishi, Y. Igarashi, M. Hirama, Tetrahedron Lett. 1994, 35, 8233; f) T. E. Horstmann, D. J. Guerin, S. J. Miller, Angew. Chem. Int. Ed. 2000, 39, 3635; g) D. J. Guerin, S. J. Miller, J. Am. Chem. Soc. 2002, 124, 2134; h) B. List, P. Pojarliev, H. J. Martin, Org. Lett. 2001, 3, 2423; i) D. Enders, A. Seki, Synlett 2002, 26; j) A. Alexakis, O. Andrey, Org. Lett. 2002, 4, 3611; k) O. Andrey, A. Alexakis, G. Bernardinelli, Org. Lett. 2003, 5, 2559; l) H. Brunner, C. Krumey, J. Mol. Catal. A 1999, 142, 7; m) J. M. Betancort, C. F. Barbas III, Org. Lett. 2001, 3, 3737; n) S. P. Brown, N. C. Goodwin, D. W. C. MacMillan, J. Am. Chem. Soc. 2003, 125, 1192; o) N. A. Paras, D. W. C. Mac-Millan, J. Am. Chem. Soc. 2002, 124, 7894; p) N. A. Paras, D. W. C. MacMillan, J. Am. Chem. Soc. 2001, 125, 4370; q) J. F. Austin, D. W. C. MacMillan, J. Am. Chem. Soc. 2002, 124, 1172; r) S. Hanessian, V. Pham, Org. Lett. 2000, 2, 2975; s) P. Bakó, T. Bakó, A. Szöllõsy, M. Czugler, G. Keglevich, L. Tóke, Tetrahedron: Asymmetry 2002, 13, 203; t) T. Perrard, J.-C. Plaquevent, J.-R. Desmurs, D. Hebrault, Org. Lett. 2000, 2, 2959; u) F.-Y. Zhang, E. J. Corey. Org. Lett. 2000, 2, 1097; v) J. M. Betancort, K. Sakthivel, R. Thayumanavan, C. F. Barbas III, Tetrahedron Lett. 2001, 42, 4441; w) P. Melchiorre, K. A. J. Jørgensen, J. Org. Chem. 2003, 65, 4151; x) E. J. Corey, M. C. Noe, F. Xu, Tetrahedron Lett. 1998, 59, 5347.
12. For examples of organocatalytic asymmetric conjugate addition reactions, see: a) M. Yamaguchi, T. Shiraishi, M. Hirama, Angew. Chem. Int. Ed. 1993, 32, 1176; b) A. Kawara, Taguchi, Tetrahedron Lett. 1994, 35, 8805; c) M. Yamaguchi, T. Shiraishi, M. Hirama, J. Org. Chem. 1996, 61, 3520; d) M. Yamaguchi, Y. Igarashi, R. S. Reddy, T. Shiraishi, M. Hirama, Tetrahedron 1997, 53, 11223; e) M. Yamaguchi, T. Shiraishi, Y. Igarashi, M. Hirama, Tetrahedron Lett. 1994, 35, 8233; f) T. E. Horstmann, D. J. Guerin, S. J. Miller, Angew. Chem. Int. Ed. 2000, 39, 3635; g) D. J. Guerin, S. J. Miller, J. Am. Chem. Soc. 2002, 124, 2134; h) B. List, P. Pojarliev, H. J. Martin, Org. Lett. 2001, 3, 2423; i) D. Enders, A. Seki, Synlett 2002, 26; j) A. Alexakis, O. Andrey, Org. Lett. 2002, 4, 3611; k) O. Andrey, A. Alexakis, G. Bernardinelli, Org. Lett. 2003, 5, 2559; l) H. Brunner, C. Krumey, J. Mol. Catal. A 1999, 142, 7; m) J. M. Betancort, C. F. Barbas III, Org. Lett. 2001, 3, 3737; n) S. P. Brown, N. C. Goodwin, D. W. C. MacMillan, J. Am. Chem. Soc. 2003, 125, 1192; o) N. A. Paras, D. W. C. Mac-Millan, J. Am. Chem. Soc. 2002, 124, 7894; p) N. A. Paras, D. W. C. MacMillan, J. Am. Chem. Soc. 2001, 125, 4370; q) J. F. Austin, D. W. C. MacMillan, J. Am. Chem. Soc. 2002, 124, 1172; r) S. Hanessian, V. Pham, Org. Lett. 2000, 2, 2975; s) P. Bakó, T. Bakó, A. Szöllõsy, M. Czugler, G. Keglevich, L. Tóke, Tetrahedron: Asymmetry 2002, 13, 203; t) T. Perrard, J.-C. Plaquevent, J.-R. Desmurs, D. Hebrault, Org. Lett. 2000, 2, 2959; u) F.-Y. Zhang, E. J. Corey. Org. Lett. 2000, 2, 1097; v) J. M. Betancort, K. Sakthivel, R. Thayumanavan, C. F. Barbas III, Tetrahedron Lett. 2001, 42, 4441; w) P. Melchiorre, K. A. J. Jørgensen, J. Org. Chem. 2003, 65, 4151; x) E. J. Corey, M. C. Noe, F. Xu, Tetrahedron Lett. 1998, 59, 5347.
13. For examples of organocatalytic asymmetric conjugate addition reactions, see: a) M. Yamaguchi, T. Shiraishi, M. Hirama, Angew. Chem. Int. Ed. 1993, 32, 1176; b) A. Kawara, Taguchi, Tetrahedron Lett. 1994, 35, 8805; c) M. Yamaguchi, T. Shiraishi, M. Hirama, J. Org. Chem. 1996, 61, 3520; d) M. Yamaguchi, Y. Igarashi, R. S. Reddy, T. Shiraishi, M. Hirama, Tetrahedron 1997, 53, 11223; e) M. Yamaguchi, T. Shiraishi, Y. Igarashi, M. Hirama, Tetrahedron Lett. 1994, 35, 8233; f) T. E. Horstmann, D. J. Guerin, S. J. Miller, Angew. Chem. Int. Ed. 2000, 39, 3635; g) D. J. Guerin, S. J. Miller, J. Am. Chem. Soc. 2002, 124, 2134; h) B. List, P. Pojarliev, H. J. Martin, Org. Lett. 2001, 3, 2423; i) D. Enders, A. Seki, Synlett 2002, 26; j) A. Alexakis, O. Andrey, Org. Lett. 2002, 4, 3611; k) O. Andrey, A. Alexakis, G. Bernardinelli, Org. Lett. 2003, 5, 2559; l) H. Brunner, C. Krumey, J. Mol. Catal. A 1999, 142, 7; m) J. M. Betancort, C. F. Barbas III, Org. Lett. 2001, 3, 3737; n) S. P. Brown, N. C. Goodwin, D. W. C. MacMillan, J. Am. Chem. Soc. 2003, 125, 1192; o) N. A. Paras, D. W. C. Mac-Millan, J. Am. Chem. Soc. 2002, 124, 7894; p) N. A. Paras, D. W. C. MacMillan, J. Am. Chem. Soc. 2001, 125, 4370; q) J. F. Austin, D. W. C. MacMillan, J. Am. Chem. Soc. 2002, 124, 1172; r) S. Hanessian, V. Pham, Org. Lett. 2000, 2, 2975; s) P. Bakó, T. Bakó, A. Szöllõsy, M. Czugler, G. Keglevich, L. Tóke, Tetrahedron: Asymmetry 2002, 13, 203; t) T. Perrard, J.-C. Plaquevent, J.-R. Desmurs, D. Hebrault, Org. Lett. 2000, 2, 2959; u) F.-Y. Zhang, E. J. Corey. Org. Lett. 2000, 2, 1097; v) J. M. Betancort, K. Sakthivel, R. Thayumanavan, C. F. Barbas III, Tetrahedron Lett. 2001, 42, 4441; w) P. Melchiorre, K. A. J. Jørgensen, J. Org. Chem. 2003, 65, 4151; x) E. J. Corey, M. C. Noe, F. Xu, Tetrahedron Lett. 1998, 59, 5347.
14. For examples of organocatalytic asymmetric conjugate addition reactions, see: a) M. Yamaguchi, T. Shiraishi, M. Hirama, Angew. Chem. Int. Ed. 1993, 32, 1176; b) A. Kawara, Taguchi, Tetrahedron Lett. 1994, 35, 8805; c) M. Yamaguchi, T. Shiraishi, M. Hirama, J. Org. Chem. 1996, 61, 3520; d) M. Yamaguchi, Y. Igarashi, R. S. Reddy, T. Shiraishi, M. Hirama, Tetrahedron 1997, 53, 11223; e) M. Yamaguchi, T. Shiraishi, Y. Igarashi, M. Hirama, Tetrahedron Lett. 1994, 35, 8233; f) T. E. Horstmann, D. J. Guerin, S. J. Miller, Angew. Chem. Int. Ed. 2000, 39, 3635; g) D. J. Guerin, S. J. Miller, J. Am. Chem. Soc. 2002, 124, 2134; h) B. List, P. Pojarliev, H. J. Martin, Org. Lett. 2001, 3, 2423; i) D. Enders, A. Seki, Synlett 2002, 26; j) A. Alexakis, O. Andrey, Org. Lett. 2002, 4, 3611; k) O. Andrey, A. Alexakis, G. Bernardinelli, Org. Lett. 2003, 5, 2559; l) H. Brunner, C. Krumey, J. Mol. Catal. A 1999, 142, 7; m) J. M. Betancort, C. F. Barbas III, Org. Lett. 2001, 3, 3737; n) S. P. Brown, N. C. Goodwin, D. W. C. MacMillan, J. Am. Chem. Soc. 2003, 125, 1192; o) N. A. Paras, D. W. C. Mac-Millan, J. Am. Chem. Soc. 2002, 124, 7894; p) N. A. Paras, D. W. C. MacMillan, J. Am. Chem. Soc. 2001, 125, 4370; q) J. F. Austin, D. W. C. MacMillan, J. Am. Chem. Soc. 2002, 124, 1172; r) S. Hanessian, V. Pham, Org. Lett. 2000, 2, 2975; s) P. Bakó, T. Bakó, A. Szöllõsy, M. Czugler, G. Keglevich, L. Tóke, Tetrahedron: Asymmetry 2002, 13, 203; t) T. Perrard, J.-C. Plaquevent, J.-R. Desmurs, D. Hebrault, Org. Lett. 2000, 2, 2959; u) F.-Y. Zhang, E. J. Corey. Org. Lett. 2000, 2, 1097; v) J. M. Betancort, K. Sakthivel, R. Thayumanavan, C. F. Barbas III, Tetrahedron Lett. 2001, 42, 4441; w) P. Melchiorre, K. A. J. Jørgensen, J. Org. Chem. 2003, 65, 4151; x) E. J. Corey, M. C. Noe, F. Xu, Tetrahedron Lett. 1998, 59, 5347.
15. For examples of organocatalytic asymmetric conjugate addition reactions, see: a) M. Yamaguchi, T. Shiraishi, M. Hirama, Angew. Chem. Int. Ed. 1993, 32, 1176; b) A. Kawara, Taguchi, Tetrahedron Lett. 1994, 35, 8805; c) M. Yamaguchi, T. Shiraishi, M. Hirama, J. Org. Chem. 1996, 61, 3520; d) M. Yamaguchi, Y. Igarashi, R. S. Reddy, T. Shiraishi, M. Hirama, Tetrahedron 1997, 53, 11223; e) M. Yamaguchi, T. Shiraishi, Y. Igarashi, M. Hirama, Tetrahedron Lett. 1994, 35, 8233; f) T. E. Horstmann, D. J. Guerin, S. J. Miller, Angew. Chem. Int. Ed. 2000, 39, 3635; g) D. J. Guerin, S. J. Miller, J. Am. Chem. Soc. 2002, 124, 2134; h) B. List, P. Pojarliev, H. J. Martin, Org. Lett. 2001, 3, 2423; i) D. Enders, A. Seki, Synlett 2002, 26; j) A. Alexakis, O. Andrey, Org. Lett. 2002, 4, 3611; k) O. Andrey, A. Alexakis, G. Bernardinelli, Org. Lett. 2003, 5, 2559; l) H. Brunner, C. Krumey, J. Mol. Catal. A 1999, 142, 7; m) J. M. Betancort, C. F. Barbas III, Org. Lett. 2001, 3, 3737; n) S. P. Brown, N. C. Goodwin, D. W. C. MacMillan, J. Am. Chem. Soc. 2003, 125, 1192; o) N. A. Paras, D. W. C. Mac-Millan, J. Am. Chem. Soc. 2002, 124, 7894; p) N. A. Paras, D. W. C. MacMillan, J. Am. Chem. Soc. 2001, 125, 4370; q) J. F. Austin, D. W. C. MacMillan, J. Am. Chem. Soc. 2002, 124, 1172; r) S. Hanessian, V. Pham, Org. Lett. 2000, 2, 2975; s) P. Bakó, T. Bakó, A. Szöllõsy, M. Czugler, G. Keglevich, L. Tóke, Tetrahedron: Asymmetry 2002, 13, 203; t) T. Perrard, J.-C. Plaquevent, J.-R. Desmurs, D. Hebrault, Org. Lett. 2000, 2, 2959; u) F.-Y. Zhang, E. J. Corey. Org. Lett. 2000, 2, 1097; v) J. M. Betancort, K. Sakthivel, R. Thayumanavan, C. F. Barbas III, Tetrahedron Lett. 2001, 42, 4441; w) P. Melchiorre, K. A. J. Jørgensen, J. Org. Chem. 2003, 65, 4151; x) E. J. Corey, M. C. Noe, F. Xu, Tetrahedron Lett. 1998, 59, 5347.
16. For examples of organocatalytic asymmetric conjugate addition reactions, see: a) M. Yamaguchi, T. Shiraishi, M. Hirama, Angew. Chem. Int. Ed. 1993, 32, 1176; b) A. Kawara, Taguchi, Tetrahedron Lett. 1994, 35, 8805; c) M. Yamaguchi, T. Shiraishi, M. Hirama, J. Org. Chem. 1996, 61, 3520; d) M. Yamaguchi, Y. Igarashi, R. S. Reddy, T. Shiraishi, M. Hirama, Tetrahedron 1997, 53, 11223; e) M. Yamaguchi, T. Shiraishi, Y. Igarashi, M. Hirama, Tetrahedron Lett. 1994, 35, 8233; f) T. E. Horstmann, D. J. Guerin, S. J. Miller, Angew. Chem. Int. Ed. 2000, 39, 3635; g) D. J. Guerin, S. J. Miller, J. Am. Chem. Soc. 2002, 124, 2134; h) B. List, P. Pojarliev, H. J. Martin, Org. Lett. 2001, 3, 2423; i) D. Enders, A. Seki, Synlett 2002, 26; j) A. Alexakis, O. Andrey, Org. Lett. 2002, 4, 3611; k) O. Andrey, A. Alexakis, G. Bernardinelli, Org. Lett. 2003, 5, 2559; l) H. Brunner, C. Krumey, J. Mol. Catal. A 1999, 142, 7; m) J. M. Betancort, C. F. Barbas III, Org. Lett. 2001, 3, 3737; n) S. P. Brown, N. C. Goodwin, D. W. C. MacMillan, J. Am. Chem. Soc. 2003, 125, 1192; o) N. A. Paras, D. W. C. Mac-Millan, J. Am. Chem. Soc. 2002, 124, 7894; p) N. A. Paras, D. W. C. MacMillan, J. Am. Chem. Soc. 2001, 125, 4370; q) J. F. Austin, D. W. C. MacMillan, J. Am. Chem. Soc. 2002, 124, 1172; r) S. Hanessian, V. Pham, Org. Lett. 2000, 2, 2975; s) P. Bakó, T. Bakó, A. Szöllõsy, M. Czugler, G. Keglevich, L. Tóke, Tetrahedron: Asymmetry 2002, 13, 203; t) T. Perrard, J.-C. Plaquevent, J.-R. Desmurs, D. Hebrault, Org. Lett. 2000, 2, 2959; u) F.-Y. Zhang, E. J. Corey. Org. Lett. 2000, 2, 1097; v) J. M. Betancort, K. Sakthivel, R. Thayumanavan, C. F. Barbas III, Tetrahedron Lett. 2001, 42, 4441; w) P. Melchiorre, K. A. J. Jørgensen, J. Org. Chem. 2003, 65, 4151; x) E. J. Corey, M. C. Noe, F. Xu, Tetrahedron Lett. 1998, 59, 5347.
17. For examples of organocatalytic asymmetric conjugate addition reactions, see: a) M. Yamaguchi, T. Shiraishi, M. Hirama, Angew. Chem. Int. Ed. 1993, 32, 1176; b) A. Kawara, Taguchi, Tetrahedron Lett. 1994, 35, 8805; c) M. Yamaguchi, T. Shiraishi, M. Hirama, J. Org. Chem. 1996, 61, 3520; d) M. Yamaguchi, Y. Igarashi, R. S. Reddy, T. Shiraishi, M. Hirama, Tetrahedron 1997, 53, 11223; e) M. Yamaguchi, T. Shiraishi, Y. Igarashi, M. Hirama, Tetrahedron Lett. 1994, 35, 8233; f) T. E. Horstmann, D. J. Guerin, S. J. Miller, Angew. Chem. Int. Ed. 2000, 39, 3635; g) D. J. Guerin, S. J. Miller, J. Am. Chem. Soc. 2002, 124, 2134; h) B. List, P. Pojarliev, H. J. Martin, Org. Lett. 2001, 3, 2423; i) D. Enders, A. Seki, Synlett 2002, 26; j) A. Alexakis, O. Andrey, Org. Lett. 2002, 4, 3611; k) O. Andrey, A. Alexakis, G. Bernardinelli, Org. Lett. 2003, 5, 2559; l) H. Brunner, C. Krumey, J. Mol. Catal. A 1999, 142, 7; m) J. M. Betancort, C. F. Barbas III, Org. Lett. 2001, 3, 3737; n) S. P. Brown, N. C. Goodwin, D. W. C. MacMillan, J. Am. Chem. Soc. 2003, 125, 1192; o) N. A. Paras, D. W. C. Mac-Millan, J. Am. Chem. Soc. 2002, 124, 7894; p) N. A. Paras, D. W. C. MacMillan, J. Am. Chem. Soc. 2001, 125, 4370; q) J. F. Austin, D. W. C. MacMillan, J. Am. Chem. Soc. 2002, 124, 1172; r) S. Hanessian, V. Pham, Org. Lett. 2000, 2, 2975; s) P. Bakó, T. Bakó, A. Szöllõsy, M. Czugler, G. Keglevich, L. Tóke, Tetrahedron: Asymmetry 2002, 13, 203; t) T. Perrard, J.-C. Plaquevent, J.-R. Desmurs, D. Hebrault, Org. Lett. 2000, 2, 2959; u) F.-Y. Zhang, E. J. Corey. Org. Lett. 2000, 2, 1097; v) J. M. Betancort, K. Sakthivel, R. Thayumanavan, C. F. Barbas III, Tetrahedron Lett. 2001, 42, 4441; w) P. Melchiorre, K. A. J. Jørgensen, J. Org. Chem. 2003, 65, 4151; x) E. J. Corey, M. C. Noe, F. Xu, Tetrahedron Lett. 1998, 59, 5347.
18. For examples of organocatalytic asymmetric conjugate addition reactions, see: a) M. Yamaguchi, T. Shiraishi, M. Hirama, Angew. Chem. Int. Ed. 1993, 32, 1176; b) A. Kawara, Taguchi, Tetrahedron Lett. 1994, 35, 8805; c) M. Yamaguchi, T. Shiraishi, M. Hirama, J. Org. Chem. 1996, 61, 3520; d) M. Yamaguchi, Y. Igarashi, R. S. Reddy, T. Shiraishi, M. Hirama, Tetrahedron 1997, 53, 11223; e) M. Yamaguchi, T. Shiraishi, Y. Igarashi, M. Hirama, Tetrahedron Lett. 1994, 35, 8233; f) T. E. Horstmann, D. J. Guerin, S. J. Miller, Angew. Chem. Int. Ed. 2000, 39, 3635; g) D. J. Guerin, S. J. Miller, J. Am. Chem. Soc. 2002, 124, 2134; h) B. List, P. Pojarliev, H. J. Martin, Org. Lett. 2001, 3, 2423; i) D. Enders, A. Seki, Synlett 2002, 26; j) A. Alexakis, O. Andrey, Org. Lett. 2002, 4, 3611; k) O. Andrey, A. Alexakis, G. Bernardinelli, Org. Lett. 2003, 5, 2559; l) H. Brunner, C. Krumey, J. Mol. Catal. A 1999, 142, 7; m) J. M. Betancort, C. F. Barbas III, Org. Lett. 2001, 3, 3737; n) S. P. Brown, N. C. Goodwin, D. W. C. MacMillan, J. Am. Chem. Soc. 2003, 125, 1192; o) N. A. Paras, D. W. C. Mac-Millan, J. Am. Chem. Soc. 2002, 124, 7894; p) N. A. Paras, D. W. C. MacMillan, J. Am. Chem. Soc. 2001, 125, 4370; q) J. F. Austin, D. W. C. MacMillan, J. Am. Chem. Soc. 2002, 124, 1172; r) S. Hanessian, V. Pham, Org. Lett. 2000, 2, 2975; s) P. Bakó, T. Bakó, A. Szöllõsy, M. Czugler, G. Keglevich, L. Tóke, Tetrahedron: Asymmetry 2002, 13, 203; t) T. Perrard, J.-C. Plaquevent, J.-R. Desmurs, D. Hebrault, Org. Lett. 2000, 2, 2959; u) F.-Y. Zhang, E. J. Corey. Org. Lett. 2000, 2, 1097; v) J. M. Betancort, K. Sakthivel, R. Thayumanavan, C. F. Barbas III, Tetrahedron Lett. 2001, 42, 4441; w) P. Melchiorre, K. A. J. Jørgensen, J. Org. Chem. 2003, 65, 4151; x) E. J. Corey, M. C. Noe, F. Xu, Tetrahedron Lett. 1998, 59, 5347.
19. For examples of organocatalytic asymmetric conjugate addition reactions, see: a) M. Yamaguchi, T. Shiraishi, M. Hirama, Angew. Chem. Int. Ed. 1993, 32, 1176; b) A. Kawara, Taguchi, Tetrahedron Lett. 1994, 35, 8805; c) M. Yamaguchi, T. Shiraishi, M. Hirama, J. Org. Chem. 1996, 61, 3520; d) M. Yamaguchi, Y. Igarashi, R. S. Reddy, T. Shiraishi, M. Hirama, Tetrahedron 1997, 53, 11223; e) M. Yamaguchi, T. Shiraishi, Y. Igarashi, M. Hirama, Tetrahedron Lett. 1994, 35, 8233; f) T. E. Horstmann, D. J. Guerin, S. J. Miller, Angew. Chem. Int. Ed. 2000, 39, 3635; g) D. J. Guerin, S. J. Miller, J. Am. Chem. Soc. 2002, 124, 2134; h) B. List, P. Pojarliev, H. J. Martin, Org. Lett. 2001, 3, 2423; i) D. Enders, A. Seki, Synlett 2002, 26; j) A. Alexakis, O. Andrey, Org. Lett. 2002, 4, 3611; k) O. Andrey, A. Alexakis, G. Bernardinelli, Org. Lett. 2003, 5, 2559; l) H. Brunner, C. Krumey, J. Mol. Catal. A 1999, 142, 7; m) J. M. Betancort, C. F. Barbas III, Org. Lett. 2001, 3, 3737; n) S. P. Brown, N. C. Goodwin, D. W. C. MacMillan, J. Am. Chem. Soc. 2003, 125, 1192; o) N. A. Paras, D. W. C. Mac-Millan, J. Am. Chem. Soc. 2002, 124, 7894; p) N. A. Paras, D. W. C. MacMillan, J. Am. Chem. Soc. 2001, 125, 4370; q) J. F. Austin, D. W. C. MacMillan, J. Am. Chem. Soc. 2002, 124, 1172; r) S. Hanessian, V. Pham, Org. Lett. 2000, 2, 2975; s) P. Bakó, T. Bakó, A. Szöllõsy, M. Czugler, G. Keglevich, L. Tóke, Tetrahedron: Asymmetry 2002, 13, 203; t) T. Perrard, J.-C. Plaquevent, J.-R. Desmurs, D. Hebrault, Org. Lett. 2000, 2, 2959; u) F.-Y. Zhang, E. J. Corey. Org. Lett. 2000, 2, 1097; v) J. M. Betancort, K. Sakthivel, R. Thayumanavan, C. F. Barbas III, Tetrahedron Lett. 2001, 42, 4441; w) P. Melchiorre, K. A. J. Jørgensen, J. Org. Chem. 2003, 65, 4151; x) E. J. Corey, M. C. Noe, F. Xu, Tetrahedron Lett. 1998, 59, 5347.
20. For examples of organocatalytic asymmetric conjugate addition reactions, see: a) M. Yamaguchi, T. Shiraishi, M. Hirama, Angew. Chem. Int. Ed. 1993, 32, 1176; b) A. Kawara, Taguchi, Tetrahedron Lett. 1994, 35, 8805; c) M. Yamaguchi, T. Shiraishi, M. Hirama, J. Org. Chem. 1996, 61, 3520; d) M. Yamaguchi, Y. Igarashi, R. S. Reddy, T. Shiraishi, M. Hirama, Tetrahedron 1997, 53, 11223; e) M. Yamaguchi, T. Shiraishi, Y. Igarashi, M. Hirama, Tetrahedron Lett. 1994, 35, 8233; f) T. E. Horstmann, D. J. Guerin, S. J. Miller, Angew. Chem. Int. Ed. 2000, 39, 3635; g) D. J. Guerin, S. J. Miller, J. Am. Chem. Soc. 2002, 124, 2134; h) B. List, P. Pojarliev, H. J. Martin, Org. Lett. 2001, 3, 2423; i) D. Enders, A. Seki, Synlett 2002, 26; j) A. Alexakis, O. Andrey, Org. Lett. 2002, 4, 3611; k) O. Andrey, A. Alexakis, G. Bernardinelli, Org. Lett. 2003, 5, 2559; l) H. Brunner, C. Krumey, J. Mol. Catal. A 1999, 142, 7; m) J. M. Betancort, C. F. Barbas III, Org. Lett. 2001, 3, 3737; n) S. P. Brown, N. C. Goodwin, D. W. C. MacMillan, J. Am. Chem. Soc. 2003, 125, 1192; o) N. A. Paras, D. W. C. Mac-Millan, J. Am. Chem. Soc. 2002, 124, 7894; p) N. A. Paras, D. W. C. MacMillan, J. Am. Chem. Soc. 2001, 125, 4370; q) J. F. Austin, D. W. C. MacMillan, J. Am. Chem. Soc. 2002, 124, 1172; r) S. Hanessian, V. Pham, Org. Lett. 2000, 2, 2975; s) P. Bakó, T. Bakó, A. Szöllõsy, M. Czugler, G. Keglevich, L. Tóke, Tetrahedron: Asymmetry 2002, 13, 203; t) T. Perrard, J.-C. Plaquevent, J.-R. Desmurs, D. Hebrault, Org. Lett. 2000, 2, 2959; u) F.-Y. Zhang, E. J. Corey. Org. Lett. 2000, 2, 1097; v) J. M. Betancort, K. Sakthivel, R. Thayumanavan, C. F. Barbas III, Tetrahedron Lett. 2001, 42, 4441; w) P. Melchiorre, K. A. J. Jørgensen, J. Org. Chem. 2003, 65, 4151; x) E. J. Corey, M. C. Noe, F. Xu, Tetrahedron Lett. 1998, 59, 5347.
21. For examples of organocatalytic asymmetric conjugate addition reactions, see: a) M. Yamaguchi, T. Shiraishi, M. Hirama, Angew. Chem. Int. Ed. 1993, 32, 1176; b) A. Kawara, Taguchi, Tetrahedron Lett. 1994, 35, 8805; c) M. Yamaguchi, T. Shiraishi, M. Hirama, J. Org. Chem. 1996, 61, 3520; d) M. Yamaguchi, Y. Igarashi, R. S. Reddy, T. Shiraishi, M. Hirama, Tetrahedron 1997, 53, 11223; e) M. Yamaguchi, T. Shiraishi, Y. Igarashi, M. Hirama, Tetrahedron Lett. 1994, 35, 8233; f) T. E. Horstmann, D. J. Guerin, S. J. Miller, Angew. Chem. Int. Ed. 2000, 39, 3635; g) D. J. Guerin, S. J. Miller, J. Am. Chem. Soc. 2002, 124, 2134; h) B. List, P. Pojarliev, H. J. Martin, Org. Lett. 2001, 3, 2423; i) D. Enders, A. Seki, Synlett 2002, 26; j) A. Alexakis, O. Andrey, Org. Lett. 2002, 4, 3611; k) O. Andrey, A. Alexakis, G. Bernardinelli, Org. Lett. 2003, 5, 2559; l) H. Brunner, C. Krumey, J. Mol. Catal. A 1999, 142, 7; m) J. M. Betancort, C. F. Barbas III, Org. Lett. 2001, 3, 3737; n) S. P. Brown, N. C. Goodwin, D. W. C. MacMillan, J. Am. Chem. Soc. 2003, 125, 1192; o) N. A. Paras, D. W. C. Mac-Millan, J. Am. Chem. Soc. 2002, 124, 7894; p) N. A. Paras, D. W. C. MacMillan, J. Am. Chem. Soc. 2001, 125, 4370; q) J. F. Austin, D. W. C. MacMillan, J. Am. Chem. Soc. 2002, 124, 1172; r) S. Hanessian, V. Pham, Org. Lett. 2000, 2, 2975; s) P. Bakó, T. Bakó, A. Szöllõsy, M. Czugler, G. Keglevich, L. Tóke, Tetrahedron: Asymmetry 2002, 13, 203; t) T. Perrard, J.-C. Plaquevent, J.-R. Desmurs, D. Hebrault, Org. Lett. 2000, 2, 2959; u) F.-Y. Zhang, E. J. Corey. Org. Lett. 2000, 2, 1097; v) J. M. Betancort, K. Sakthivel, R. Thayumanavan, C. F. Barbas III, Tetrahedron Lett. 2001, 42, 4441; w) P. Melchiorre, K. A. J. Jørgensen, J. Org. Chem. 2003, 65, 4151; x) E. J. Corey, M. C. Noe, F. Xu, Tetrahedron Lett. 1998, 59, 5347.
22. For examples of organocatalytic asymmetric conjugate addition reactions, see: a) M. Yamaguchi, T. Shiraishi, M. Hirama, Angew. Chem. Int. Ed. 1993, 32, 1176; b) A. Kawara, Taguchi, Tetrahedron Lett. 1994, 35, 8805; c) M. Yamaguchi, T. Shiraishi, M. Hirama, J. Org. Chem. 1996, 61, 3520; d) M. Yamaguchi, Y. Igarashi, R. S. Reddy, T. Shiraishi, M. Hirama, Tetrahedron 1997, 53, 11223; e) M. Yamaguchi, T. Shiraishi, Y. Igarashi, M. Hirama, Tetrahedron Lett. 1994, 35, 8233; f) T. E. Horstmann, D. J. Guerin, S. J. Miller, Angew. Chem. Int. Ed. 2000, 39, 3635; g) D. J. Guerin, S. J. Miller, J. Am. Chem. Soc. 2002, 124, 2134; h) B. List, P. Pojarliev, H. J. Martin, Org. Lett. 2001, 3, 2423; i) D. Enders, A. Seki, Synlett 2002, 26; j) A. Alexakis, O. Andrey, Org. Lett. 2002, 4, 3611; k) O. Andrey, A. Alexakis, G. Bernardinelli, Org. Lett. 2003, 5, 2559; l) H. Brunner, C. Krumey, J. Mol. Catal. A 1999, 142, 7; m) J. M. Betancort, C. F. Barbas III, Org. Lett. 2001, 3, 3737; n) S. P. Brown, N. C. Goodwin, D. W. C. MacMillan, J. Am. Chem. Soc. 2003, 125, 1192; o) N. A. Paras, D. W. C. Mac-Millan, J. Am. Chem. Soc. 2002, 124, 7894; p) N. A. Paras, D. W. C. MacMillan, J. Am. Chem. Soc. 2001, 125, 4370; q) J. F. Austin, D. W. C. MacMillan, J. Am. Chem. Soc. 2002, 124, 1172; r) S. Hanessian, V. Pham, Org. Lett. 2000, 2, 2975; s) P. Bakó, T. Bakó, A. Szöllõsy, M. Czugler, G. Keglevich, L. Tóke, Tetrahedron: Asymmetry 2002, 13, 203; t) T. Perrard, J.-C. Plaquevent, J.-R. Desmurs, D. Hebrault, Org. Lett. 2000, 2, 2959; u) F.-Y. Zhang, E. J. Corey. Org. Lett. 2000, 2, 1097; v) J. M. Betancort, K. Sakthivel, R. Thayumanavan, C. F. Barbas III, Tetrahedron Lett. 2001, 42, 4441; w) P. Melchiorre, K. A. J. Jørgensen, J. Org. Chem. 2003, 65, 4151; x) E. J. Corey, M. C. Noe, F. Xu, Tetrahedron Lett. 1998, 59, 5347.
23. For examples of organocatalytic asymmetric conjugate addition reactions, see: a) M. Yamaguchi, T. Shiraishi, M. Hirama, Angew. Chem. Int. Ed. 1993, 32, 1176; b) A. Kawara, Taguchi, Tetrahedron Lett. 1994, 35, 8805; c) M. Yamaguchi, T. Shiraishi, M. Hirama, J. Org. Chem. 1996, 61, 3520; d) M. Yamaguchi, Y. Igarashi, R. S. Reddy, T. Shiraishi, M. Hirama, Tetrahedron 1997, 53, 11223; e) M. Yamaguchi, T. Shiraishi, Y. Igarashi, M. Hirama, Tetrahedron Lett. 1994, 35, 8233; f) T. E. Horstmann, D. J. Guerin, S. J. Miller, Angew. Chem. Int. Ed. 2000, 39, 3635; g) D. J. Guerin, S. J. Miller, J. Am. Chem. Soc. 2002, 124, 2134; h) B. List, P. Pojarliev, H. J. Martin, Org. Lett. 2001, 3, 2423; i) D. Enders, A. Seki, Synlett 2002, 26; j) A. Alexakis, O. Andrey, Org. Lett. 2002, 4, 3611; k) O. Andrey, A. Alexakis, G. Bernardinelli, Org. Lett. 2003, 5, 2559; l) H. Brunner, C. Krumey, J. Mol. Catal. A 1999, 142, 7; m) J. M. Betancort, C. F. Barbas III, Org. Lett. 2001, 3, 3737; n) S. P. Brown, N. C. Goodwin, D. W. C. MacMillan, J. Am. Chem. Soc. 2003, 125, 1192; o) N. A. Paras, D. W. C. Mac-Millan, J. Am. Chem. Soc. 2002, 124, 7894; p) N. A. Paras, D. W. C. MacMillan, J. Am. Chem. Soc. 2001, 125, 4370; q) J. F. Austin, D. W. C. MacMillan, J. Am. Chem. Soc. 2002, 124, 1172; r) S. Hanessian, V. Pham, Org. Lett. 2000, 2, 2975; s) P. Bakó, T. Bakó, A. Szöllõsy, M. Czugler, G. Keglevich, L. Tóke, Tetrahedron: Asymmetry 2002, 13, 203; t) T. Perrard, J.-C. Plaquevent, J.-R. Desmurs, D. Hebrault, Org. Lett. 2000, 2, 2959; u) F.-Y. Zhang, E. J. Corey. Org. Lett. 2000, 2, 1097; v) J. M. Betancort, K. Sakthivel, R. Thayumanavan, C. F. Barbas III, Tetrahedron Lett. 2001, 42, 4441; w) P. Melchiorre, K. A. J. Jørgensen, J. Org. Chem. 2003, 65, 4151; x) E. J. Corey, M. C. Noe, F. Xu, Tetrahedron Lett. 1998, 59, 5347.
24. For examples of organocatalytic asymmetric conjugate addition reactions, see: a) M. Yamaguchi, T. Shiraishi, M. Hirama, Angew. Chem. Int. Ed. 1993, 32, 1176; b) A. Kawara, Taguchi, Tetrahedron Lett. 1994, 35, 8805; c) M. Yamaguchi, T. Shiraishi, M. Hirama, J. Org. Chem. 1996, 61, 3520; d) M. Yamaguchi, Y. Igarashi, R. S. Reddy, T. Shiraishi, M. Hirama, Tetrahedron 1997, 53, 11223; e) M. Yamaguchi, T. Shiraishi, Y. Igarashi, M. Hirama, Tetrahedron Lett. 1994, 35, 8233; f) T. E. Horstmann, D. J. Guerin, S. J. Miller, Angew. Chem. Int. Ed. 2000, 39, 3635; g) D. J. Guerin, S. J. Miller, J. Am. Chem. Soc. 2002, 124, 2134; h) B. List, P. Pojarliev, H. J. Martin, Org. Lett. 2001, 3, 2423; i) D. Enders, A. Seki, Synlett 2002, 26; j) A. Alexakis, O. Andrey, Org. Lett. 2002, 4, 3611; k) O. Andrey, A. Alexakis, G. Bernardinelli, Org. Lett. 2003, 5, 2559; l) H. Brunner, C. Krumey, J. Mol. Catal. A 1999, 142, 7; m) J. M. Betancort, C. F. Barbas III, Org. Lett. 2001, 3, 3737; n) S. P. Brown, N. C. Goodwin, D. W. C. MacMillan, J. Am. Chem. Soc. 2003, 125, 1192; o) N. A. Paras, D. W. C. Mac-Millan, J. Am. Chem. Soc. 2002, 124, 7894; p) N. A. Paras, D. W. C. MacMillan, J. Am. Chem. Soc. 2001, 125, 4370; q) J. F. Austin, D. W. C. MacMillan, J. Am. Chem. Soc. 2002, 124, 1172; r) S. Hanessian, V. Pham, Org. Lett. 2000, 2, 2975; s) P. Bakó, T. Bakó, A. Szöllõsy, M. Czugler, G. Keglevich, L. Tóke, Tetrahedron: Asymmetry 2002, 13, 203; t) T. Perrard, J.-C. Plaquevent, J.-R. Desmurs, D. Hebrault, Org. Lett. 2000, 2, 2959; u) F.-Y. Zhang, E. J. Corey. Org. Lett. 2000, 2, 1097; v) J. M. Betancort, K. Sakthivel, R. Thayumanavan, C. F. Barbas III, Tetrahedron Lett. 2001, 42, 4441; w) P. Melchiorre, K. A. J. Jørgensen, J. Org. Chem. 2003, 65, 4151; x) E. J. Corey, M. C. Noe, F. Xu, Tetrahedron Lett. 1998, 59, 5347.
25. For examples of organocatalytic asymmetric conjugate addition reactions, see: a) M. Yamaguchi, T. Shiraishi, M. Hirama, Angew. Chem. Int. Ed. 1993, 32, 1176; b) A. Kawara, Taguchi, Tetrahedron Lett. 1994, 35, 8805; c) M. Yamaguchi, T. Shiraishi, M. Hirama, J. Org. Chem. 1996, 61, 3520; d) M. Yamaguchi, Y. Igarashi, R. S. Reddy, T. Shiraishi, M. Hirama, Tetrahedron 1997, 53, 11223; e) M. Yamaguchi, T. Shiraishi, Y. Igarashi, M. Hirama, Tetrahedron Lett. 1994, 35, 8233; f) T. E. Horstmann, D. J. Guerin, S. J. Miller, Angew. Chem. Int. Ed. 2000, 39, 3635; g) D. J. Guerin, S. J. Miller, J. Am. Chem. Soc. 2002, 124, 2134; h) B. List, P. Pojarliev, H. J. Martin, Org. Lett. 2001, 3, 2423; i) D. Enders, A. Seki, Synlett 2002, 26; j) A. Alexakis, O. Andrey, Org. Lett. 2002, 4, 3611; k) O. Andrey, A. Alexakis, G. Bernardinelli, Org. Lett. 2003, 5, 2559; l) H. Brunner, C. Krumey, J. Mol. Catal. A 1999, 142, 7; m) J. M. Betancort, C. F. Barbas III, Org. Lett. 2001, 3, 3737; n) S. P. Brown, N. C. Goodwin, D. W. C. MacMillan, J. Am. Chem. Soc. 2003, 125, 1192; o) N. A. Paras, D. W. C. Mac-Millan, J. Am. Chem. Soc. 2002, 124, 7894; p) N. A. Paras, D. W. C. MacMillan, J. Am. Chem. Soc. 2001, 125, 4370; q) J. F. Austin, D. W. C. MacMillan, J. Am. Chem. Soc. 2002, 124, 1172; r) S. Hanessian, V. Pham, Org. Lett. 2000, 2, 2975; s) P. Bakó, T. Bakó, A. Szöllõsy, M. Czugler, G. Keglevich, L. Tóke, Tetrahedron: Asymmetry 2002, 13, 203; t) T. Perrard, J.-C. Plaquevent, J.-R. Desmurs, D. Hebrault, Org. Lett. 2000, 2, 2959; u) F.-Y. Zhang, E. J. Corey. Org. Lett. 2000, 2, 1097; v) J. M. Betancort, K. Sakthivel, R. Thayumanavan, C. F. Barbas III, Tetrahedron Lett. 2001, 42, 4441; w) P. Melchiorre, K. A. J. Jørgensen, J. Org. Chem. 2003, 65, 4151; x) E. J. Corey, M. C. Noe, F. Xu, Tetrahedron Lett. 1998, 59, 5347.
26. For examples of organocatalytic asymmetric conjugate addition reactions, see: a) M. Yamaguchi, T. Shiraishi, M. Hirama, Angew. Chem. Int. Ed. 1993, 32, 1176; b) A. Kawara, Taguchi, Tetrahedron Lett. 1994, 35, 8805; c) M. Yamaguchi, T. Shiraishi, M. Hirama, J. Org. Chem. 1996, 61, 3520; d) M. Yamaguchi, Y. Igarashi, R. S. Reddy, T. Shiraishi, M. Hirama, Tetrahedron 1997, 53, 11223; e) M. Yamaguchi, T. Shiraishi, Y. Igarashi, M. Hirama, Tetrahedron Lett. 1994, 35, 8233; f) T. E. Horstmann, D. J. Guerin, S. J. Miller, Angew. Chem. Int. Ed. 2000, 39, 3635; g) D. J. Guerin, S. J. Miller, J. Am. Chem. Soc. 2002, 124, 2134; h) B. List, P. Pojarliev, H. J. Martin, Org. Lett. 2001, 3, 2423; i) D. Enders, A. Seki, Synlett 2002, 26; j) A. Alexakis, O. Andrey, Org. Lett. 2002, 4, 3611; k) O. Andrey, A. Alexakis, G. Bernardinelli, Org. Lett. 2003, 5, 2559; l) H. Brunner, C. Krumey, J. Mol. Catal. A 1999, 142, 7; m) J. M. Betancort, C. F. Barbas III, Org. Lett. 2001, 3, 3737; n) S. P. Brown, N. C. Goodwin, D. W. C. MacMillan, J. Am. Chem. Soc. 2003, 125, 1192; o) N. A. Paras, D. W. C. Mac-Millan, J. Am. Chem. Soc. 2002, 124, 7894; p) N. A. Paras, D. W. C. MacMillan, J. Am. Chem. Soc. 2001, 125, 4370; q) J. F. Austin, D. W. C. MacMillan, J. Am. Chem. Soc. 2002, 124, 1172; r) S. Hanessian, V. Pham, Org. Lett. 2000, 2, 2975; s) P. Bakó, T. Bakó, A. Szöllõsy, M. Czugler, G. Keglevich, L. Tóke, Tetrahedron: Asymmetry 2002, 13, 203; t) T. Perrard, J.-C. Plaquevent, J.-R. Desmurs, D. Hebrault, Org. Lett. 2000, 2, 2959; u) F.-Y. Zhang, E. J. Corey. Org. Lett. 2000, 2, 1097; v) J. M. Betancort, K. Sakthivel, R. Thayumanavan, C. F. Barbas III, Tetrahedron Lett. 2001, 42, 4441; w) P. Melchiorre, K. A. J. Jørgensen, J. Org. Chem. 2003, 65, 4151; x) E. J. Corey, M. C. Noe, F. Xu, Tetrahedron Lett. 1998, 59, 5347.
27. For examples of organocatalytic asymmetric conjugate addition reactions, see: a) M. Yamaguchi, T. Shiraishi, M. Hirama, Angew. Chem. Int. Ed. 1993, 32, 1176; b) A. Kawara, Taguchi, Tetrahedron Lett. 1994, 35, 8805; c) M. Yamaguchi, T. Shiraishi, M. Hirama, J. Org. Chem. 1996, 61, 3520; d) M. Yamaguchi, Y. Igarashi, R. S. Reddy, T. Shiraishi, M. Hirama, Tetrahedron 1997, 53, 11223; e) M. Yamaguchi, T. Shiraishi, Y. Igarashi, M. Hirama, Tetrahedron Lett. 1994, 35, 8233; f) T. E. Horstmann, D. J. Guerin, S. J. Miller, Angew. Chem. Int. Ed. 2000, 39, 3635; g) D. J. Guerin, S. J. Miller, J. Am. Chem. Soc. 2002, 124, 2134; h) B. List, P. Pojarliev, H. J. Martin, Org. Lett. 2001, 3, 2423; i) D. Enders, A. Seki, Synlett 2002, 26; j) A. Alexakis, O. Andrey, Org. Lett. 2002, 4, 3611; k) O. Andrey, A. Alexakis, G. Bernardinelli, Org. Lett. 2003, 5, 2559; l) H. Brunner, C. Krumey, J. Mol. Catal. A 1999, 142, 7; m) J. M. Betancort, C. F. Barbas III, Org. Lett. 2001, 3, 3737; n) S. P. Brown, N. C. Goodwin, D. W. C. MacMillan, J. Am. Chem. Soc. 2003, 125, 1192; o) N. A. Paras, D. W. C. Mac-Millan, J. Am. Chem. Soc. 2002, 124, 7894; p) N. A. Paras, D. W. C. MacMillan, J. Am. Chem. Soc. 2001, 125, 4370; q) J. F. Austin, D. W. C. MacMillan, J. Am. Chem. Soc. 2002, 124, 1172; r) S. Hanessian, V. Pham, Org. Lett. 2000, 2, 2975; s) P. Bakó, T. Bakó, A. Szöllõsy, M. Czugler, G. Keglevich, L. Tóke, Tetrahedron: Asymmetry 2002, 13, 203; t) T. Perrard, J.-C. Plaquevent, J.-R. Desmurs, D. Hebrault, Org. Lett. 2000, 2, 2959; u) F.-Y. Zhang, E. J. Corey. Org. Lett. 2000, 2, 1097; v) J. M. Betancort, K. Sakthivel, R. Thayumanavan, C. F. Barbas III, Tetrahedron Lett. 2001, 42, 4441; w) P. Melchiorre, K. A. J. Jørgensen, J. Org. Chem. 2003, 65, 4151; x) E. J. Corey, M. C. Noe, F. Xu, Tetrahedron Lett. 1998, 59, 5347.
28. For examples of organocatalytic asymmetric conjugate addition reactions, see: a) M. Yamaguchi, T. Shiraishi, M. Hirama, Angew. Chem. Int. Ed. 1993, 32, 1176; b) A. Kawara, Taguchi, Tetrahedron Lett. 1994, 35, 8805; c) M. Yamaguchi, T. Shiraishi, M. Hirama, J. Org. Chem. 1996, 61, 3520; d) M. Yamaguchi, Y. Igarashi, R. S. Reddy, T. Shiraishi, M. Hirama, Tetrahedron 1997, 53, 11223; e) M. Yamaguchi, T. Shiraishi, Y. Igarashi, M. Hirama, Tetrahedron Lett. 1994, 35, 8233; f) T. E. Horstmann, D. J. Guerin, S. J. Miller, Angew. Chem. Int. Ed. 2000, 39, 3635; g) D. J. Guerin, S. J. Miller, J. Am. Chem. Soc. 2002, 124, 2134; h) B. List, P. Pojarliev, H. J. Martin, Org. Lett. 2001, 3, 2423; i) D. Enders, A. Seki, Synlett 2002, 26; j) A. Alexakis, O. Andrey, Org. Lett. 2002, 4, 3611; k) O. Andrey, A. Alexakis, G. Bernardinelli, Org. Lett. 2003, 5, 2559; l) H. Brunner, C. Krumey, J. Mol. Catal. A 1999, 142, 7; m) J. M. Betancort, C. F. Barbas III, Org. Lett. 2001, 3, 3737; n) S. P. Brown, N. C. Goodwin, D. W. C. MacMillan, J. Am. Chem. Soc. 2003, 125, 1192; o) N. A. Paras, D. W. C. Mac-Millan, J. Am. Chem. Soc. 2002, 124, 7894; p) N. A. Paras, D. W. C. MacMillan, J. Am. Chem. Soc. 2001, 125, 4370; q) J. F. Austin, D. W. C. MacMillan, J. Am. Chem. Soc. 2002, 124, 1172; r) S. Hanessian, V. Pham, Org. Lett. 2000, 2, 2975; s) P. Bakó, T. Bakó, A. Szöllõsy, M. Czugler, G. Keglevich, L. Tóke, Tetrahedron: Asymmetry 2002, 13, 203; t) T. Perrard, J.-C. Plaquevent, J.-R. Desmurs, D. Hebrault, Org. Lett. 2000, 2, 2959; u) F.-Y. Zhang, E. J. Corey. Org. Lett. 2000, 2, 1097; v) J. M. Betancort, K. Sakthivel, R. Thayumanavan, C. F. Barbas III, Tetrahedron Lett. 2001, 42, 4441; w) P. Melchiorre, K. A. J. Jørgensen, J. Org. Chem. 2003, 65, 4151; x) E. J. Corey, M. C. Noe, F. Xu, Tetrahedron Lett. 1998, 59, 5347.
29. For examples of organocatalytic asymmetric conjugate addition reactions, see: a) M. Yamaguchi, T. Shiraishi, M. Hirama, Angew. Chem. Int. Ed. 1993, 32, 1176; b) A. Kawara, Taguchi, Tetrahedron Lett. 1994, 35, 8805; c) M. Yamaguchi, T. Shiraishi, M. Hirama, J. Org. Chem. 1996, 61, 3520; d) M. Yamaguchi, Y. Igarashi, R. S. Reddy, T. Shiraishi, M. Hirama, Tetrahedron 1997, 53, 11223; e) M. Yamaguchi, T. Shiraishi, Y. Igarashi, M. Hirama, Tetrahedron Lett. 1994, 35, 8233; f) T. E. Horstmann, D. J. Guerin, S. J. Miller, Angew. Chem. Int. Ed. 2000, 39, 3635; g) D. J. Guerin, S. J. Miller, J. Am. Chem. Soc. 2002, 124, 2134; h) B. List, P. Pojarliev, H. J. Martin, Org. Lett. 2001, 3, 2423; i) D. Enders, A. Seki, Synlett 2002, 26; j) A. Alexakis, O. Andrey, Org. Lett. 2002, 4, 3611; k) O. Andrey, A. Alexakis, G. Bernardinelli, Org. Lett. 2003, 5, 2559; l) H. Brunner, C. Krumey, J. Mol. Catal. A 1999, 142, 7; m) J. M. Betancort, C. F. Barbas III, Org. Lett. 2001, 3, 3737; n) S. P. Brown, N. C. Goodwin, D. W. C. MacMillan, J. Am. Chem. Soc. 2003, 125, 1192; o) N. A. Paras, D. W. C. Mac-Millan, J. Am. Chem. Soc. 2002, 124, 7894; p) N. A. Paras, D. W. C. MacMillan, J. Am. Chem. Soc. 2001, 125, 4370; q) J. F. Austin, D. W. C. MacMillan, J. Am. Chem. Soc. 2002, 124, 1172; r) S. Hanessian, V. Pham, Org. Lett. 2000, 2, 2975; s) P. Bakó, T. Bakó, A. Szöllõsy, M. Czugler, G. Keglevich, L. Tóke, Tetrahedron: Asymmetry 2002, 13, 203; t) T. Perrard, J.-C. Plaquevent, J.-R. Desmurs, D. Hebrault, Org. Lett. 2000, 2, 2959; u) F.-Y. Zhang, E. J. Corey. Org. Lett. 2000, 2, 1097; v) J. M. Betancort, K. Sakthivel, R. Thayumanavan, C. F. Barbas III, Tetrahedron Lett. 2001, 42, 4441; w) P. Melchiorre, K. A. J. Jørgensen, J. Org. Chem. 2003, 65, 4151; x) E. J. Corey, M. C. Noe, F. Xu, Tetrahedron Lett. 1998, 59, 5347.
30. For examples of organocatalytic asymmetric conjugate addition reactions, see: a) M. Yamaguchi, T. Shiraishi, M. Hirama, Angew. Chem. Int. Ed. 1993, 32, 1176; b) A. Kawara, Taguchi, Tetrahedron Lett. 1994, 35, 8805; c) M. Yamaguchi, T. Shiraishi, M. Hirama, J. Org. Chem. 1996, 61, 3520; d) M. Yamaguchi, Y. Igarashi, R. S. Reddy, T. Shiraishi, M. Hirama, Tetrahedron 1997, 53, 11223; e) M. Yamaguchi, T. Shiraishi, Y. Igarashi, M. Hirama, Tetrahedron Lett. 1994, 35, 8233; f) T. E. Horstmann, D. J. Guerin, S. J. Miller, Angew. Chem. Int. Ed. 2000, 39, 3635; g) D. J. Guerin, S. J. Miller, J. Am. Chem. Soc. 2002, 124, 2134; h) B. List, P. Pojarliev, H. J. Martin, Org. Lett. 2001, 3, 2423; i) D. Enders, A. Seki, Synlett 2002, 26; j) A. Alexakis, O. Andrey, Org. Lett. 2002, 4, 3611; k) O. Andrey, A. Alexakis, G. Bernardinelli, Org. Lett. 2003, 5, 2559; l) H. Brunner, C. Krumey, J. Mol. Catal. A 1999, 142, 7; m) J. M. Betancort, C. F. Barbas III, Org. Lett. 2001, 3, 3737; n) S. P. Brown, N. C. Goodwin, D. W. C. MacMillan, J. Am. Chem. Soc. 2003, 125, 1192; o) N. A. Paras, D. W. C. Mac-Millan, J. Am. Chem. Soc. 2002, 124, 7894; p) N. A. Paras, D. W. C. MacMillan, J. Am. Chem. Soc. 2001, 125, 4370; q) J. F. Austin, D. W. C. MacMillan, J. Am. Chem. Soc. 2002, 124, 1172; r) S. Hanessian, V. Pham, Org. Lett. 2000, 2, 2975; s) P. Bakó, T. Bakó, A. Szöllõsy, M. Czugler, G. Keglevich, L. Tóke, Tetrahedron: Asymmetry 2002, 13, 203; t) T. Perrard, J.-C. Plaquevent, J.-R. Desmurs, D. Hebrault, Org. Lett. 2000, 2, 2959; u) F.-Y. Zhang, E. J. Corey. Org. Lett. 2000, 2, 1097; v) J. M. Betancort, K. Sakthivel, R. Thayumanavan, C. F. Barbas III, Tetrahedron Lett. 2001, 42, 4441; w) P. Melchiorre, K. A. J. Jørgensen, J. Org. Chem. 2003, 65, 4151; x) E. J. Corey, M. C. Noe, F. Xu, Tetrahedron Lett. 1998, 59, 5347.
31. For examples of organocatalytic asymmetric conjugate addition reactions, see: a) M. Yamaguchi, T. Shiraishi, M. Hirama, Angew. Chem. Int. Ed. 1993, 32, 1176; b) A. Kawara, Taguchi, Tetrahedron Lett. 1994, 35, 8805; c) M. Yamaguchi, T. Shiraishi, M. Hirama, J. Org. Chem. 1996, 61, 3520; d) M. Yamaguchi, Y. Igarashi, R. S. Reddy, T. Shiraishi, M. Hirama, Tetrahedron 1997, 53, 11223; e) M. Yamaguchi, T. Shiraishi, Y. Igarashi, M. Hirama, Tetrahedron Lett. 1994, 35, 8233; f) T. E. Horstmann, D. J. Guerin, S. J. Miller, Angew. Chem. Int. Ed. 2000, 39, 3635; g) D. J. Guerin, S. J. Miller, J. Am. Chem. Soc. 2002, 124, 2134; h) B. List, P. Pojarliev, H. J. Martin, Org. Lett. 2001, 3, 2423; i) D. Enders, A. Seki, Synlett 2002, 26; j) A. Alexakis, O. Andrey, Org. Lett. 2002, 4, 3611; k) O. Andrey, A. Alexakis, G. Bernardinelli, Org. Lett. 2003, 5, 2559; l) H. Brunner, C. Krumey, J. Mol. Catal. A 1999, 142, 7; m) J. M. Betancort, C. F. Barbas III, Org. Lett. 2001, 3, 3737; n) S. P. Brown, N. C. Goodwin, D. W. C. MacMillan, J. Am. Chem. Soc. 2003, 125, 1192; o) N. A. Paras, D. W. C. Mac-Millan, J. Am. Chem. Soc. 2002, 124, 7894; p) N. A. Paras, D. W. C. MacMillan, J. Am. Chem. Soc. 2001, 125, 4370; q) J. F. Austin, D. W. C. MacMillan, J. Am. Chem. Soc. 2002, 124, 1172; r) S. Hanessian, V. Pham, Org. Lett. 2000, 2, 2975; s) P. Bakó, T. Bakó, A. Szöllõsy, M. Czugler, G. Keglevich, L. Tóke, Tetrahedron: Asymmetry 2002, 13, 203; t) T. Perrard, J.-C. Plaquevent, J.-R. Desmurs, D. Hebrault, Org. Lett. 2000, 2, 2959; u) F.-Y. Zhang, E. J. Corey. Org. Lett. 2000, 2, 1097; v) J. M. Betancort, K. Sakthivel, R. Thayumanavan, C. F. Barbas III, Tetrahedron Lett. 2001, 42, 4441; w) P. Melchiorre, K. A. J. Jørgensen, J. Org. Chem. 2003, 65, 4151; x) E. J. Corey, M. C. Noe, F. Xu, Tetrahedron Lett. 1998, 59, 5347.
32. For examples of organocatalytic asymmetric conjugate addition reactions, see: a) M. Yamaguchi, T. Shiraishi, M. Hirama, Angew. Chem. Int. Ed. 1993, 32, 1176; b) A. Kawara, Taguchi, Tetrahedron Lett. 1994, 35, 8805; c) M. Yamaguchi, T. Shiraishi, M. Hirama, J. Org. Chem. 1996, 61, 3520; d) M. Yamaguchi, Y. Igarashi, R. S. Reddy, T. Shiraishi, M. Hirama, Tetrahedron 1997, 53, 11223; e) M. Yamaguchi, T. Shiraishi, Y. Igarashi, M. Hirama, Tetrahedron Lett. 1994, 35, 8233; f) T. E. Horstmann, D. J. Guerin, S. J. Miller, Angew. Chem. Int. Ed. 2000, 39, 3635; g) D. J. Guerin, S. J. Miller, J. Am. Chem. Soc. 2002, 124, 2134; h) B. List, P. Pojarliev, H. J. Martin, Org. Lett. 2001, 3, 2423; i) D. Enders, A. Seki, Synlett 2002, 26; j) A. Alexakis, O. Andrey, Org. Lett. 2002, 4, 3611; k) O. Andrey, A. Alexakis, G. Bernardinelli, Org. Lett. 2003, 5, 2559; l) H. Brunner, C. Krumey, J. Mol. Catal. A 1999, 142, 7; m) J. M. Betancort, C. F. Barbas III, Org. Lett. 2001, 3, 3737; n) S. P. Brown, N. C. Goodwin, D. W. C. MacMillan, J. Am. Chem. Soc. 2003, 125, 1192; o) N. A. Paras, D. W. C. Mac-Millan, J. Am. Chem. Soc. 2002, 124, 7894; p) N. A. Paras, D. W. C. MacMillan, J. Am. Chem. Soc. 2001, 125, 4370; q) J. F. Austin, D. W. C. MacMillan, J. Am. Chem. Soc. 2002, 124, 1172; r) S. Hanessian, V. Pham, Org. Lett. 2000, 2, 2975; s) P. Bakó, T. Bakó, A. Szöllõsy, M. Czugler, G. Keglevich, L. Tóke, Tetrahedron: Asymmetry 2002, 13, 203; t) T. Perrard, J.-C. Plaquevent, J.-R. Desmurs, D. Hebrault, Org. Lett. 2000, 2, 2959; u) F.-Y. Zhang, E. J. Corey. Org. Lett. 2000, 2, 1097; v) J. M. Betancort, K. Sakthivel, R. Thayumanavan, C. F. Barbas III, Tetrahedron Lett. 2001, 42, 4441; w) P. Melchiorre, K. A. J. Jørgensen, J. Org. Chem. 2003, 65, 4151; x) E. J. Corey, M. C. Noe, F. Xu, Tetrahedron Lett. 1998, 59, 5347.
33. For examples of organocatalytic asymmetric conjugate addition reactions, see: a) M. Yamaguchi, T. Shiraishi, M. Hirama, Angew. Chem. Int. Ed. 1993, 32, 1176; b) A. Kawara, Taguchi, Tetrahedron Lett. 1994, 35, 8805; c) M. Yamaguchi, T. Shiraishi, M. Hirama, J. Org. Chem. 1996, 61, 3520; d) M. Yamaguchi, Y. Igarashi, R. S. Reddy, T. Shiraishi, M. Hirama, Tetrahedron 1997, 53, 11223; e) M. Yamaguchi, T. Shiraishi, Y. Igarashi, M. Hirama, Tetrahedron Lett. 1994, 35, 8233; f) T. E. Horstmann, D. J. Guerin, S. J. Miller, Angew. Chem. Int. Ed. 2000, 39, 3635; g) D. J. Guerin, S. J. Miller, J. Am. Chem. Soc. 2002, 124, 2134; h) B. List, P. Pojarliev, H. J. Martin, Org. Lett. 2001, 3, 2423; i) D. Enders, A. Seki, Synlett 2002, 26; j) A. Alexakis, O. Andrey, Org. Lett. 2002, 4, 3611; k) O. Andrey, A. Alexakis, G. Bernardinelli, Org. Lett. 2003, 5, 2559; l) H. Brunner, C. Krumey, J. Mol. Catal. A 1999, 142, 7; m) J. M. Betancort, C. F. Barbas III, Org. Lett. 2001, 3, 3737; n) S. P. Brown, N. C. Goodwin, D. W. C. MacMillan, J. Am. Chem. Soc. 2003, 125, 1192; o) N. A. Paras, D. W. C. Mac-Millan, J. Am. Chem. Soc. 2002, 124, 7894; p) N. A. Paras, D. W. C. MacMillan, J. Am. Chem. Soc. 2001, 125, 4370; q) J. F. Austin, D. W. C. MacMillan, J. Am. Chem. Soc. 2002, 124, 1172; r) S. Hanessian, V. Pham, Org. Lett. 2000, 2, 2975; s) P. Bakó, T. Bakó, A. Szöllõsy, M. Czugler, G. Keglevich, L. Tóke, Tetrahedron: Asymmetry 2002, 13, 203; t) T. Perrard, J.-C. Plaquevent, J.-R. Desmurs, D. Hebrault, Org. Lett. 2000, 2, 2959; u) F.-Y. Zhang, E. J. Corey. Org. Lett. 2000, 2, 1097; v) J. M. Betancort, K. Sakthivel, R. Thayumanavan, C. F. Barbas III, Tetrahedron Lett. 2001, 42, 4441; w) P. Melchiorre, K. A. J. Jørgensen, J. Org. Chem. 2003, 65, 4151; x) E. J. Corey, M. C. Noe, F. Xu, Tetrahedron Lett. 1998, 59, 5347.
34. For examples of organocatalytic asymmetric conjugate addition reactions, see: a) M. Yamaguchi, T. Shiraishi, M. Hirama, Angew. Chem. Int. Ed. 1993, 32, 1176; b) A. Kawara, Taguchi, Tetrahedron Lett. 1994, 35, 8805; c) M. Yamaguchi, T. Shiraishi, M. Hirama, J. Org. Chem. 1996, 61, 3520; d) M. Yamaguchi, Y. Igarashi, R. S. Reddy, T. Shiraishi, M. Hirama, Tetrahedron 1997, 53, 11223; e) M. Yamaguchi, T. Shiraishi, Y. Igarashi, M. Hirama, Tetrahedron Lett. 1994, 35, 8233; f) T. E. Horstmann, D. J. Guerin, S. J. Miller, Angew. Chem. Int. Ed. 2000, 39, 3635; g) D. J. Guerin, S. J. Miller, J. Am. Chem. Soc. 2002, 124, 2134; h) B. List, P. Pojarliev, H. J. Martin, Org. Lett. 2001, 3, 2423; i) D. Enders, A. Seki, Synlett 2002, 26; j) A. Alexakis, O. Andrey, Org. Lett. 2002, 4, 3611; k) O. Andrey, A. Alexakis, G. Bernardinelli, Org. Lett. 2003, 5, 2559; l) H. Brunner, C. Krumey, J. Mol. Catal. A 1999, 142, 7; m) J. M. Betancort, C. F. Barbas III, Org. Lett. 2001, 3, 3737; n) S. P. Brown, N. C. Goodwin, D. W. C. MacMillan, J. Am. Chem. Soc. 2003, 125, 1192; o) N. A. Paras, D. W. C. Mac-Millan, J. Am. Chem. Soc. 2002, 124, 7894; p) N. A. Paras, D. W. C. MacMillan, J. Am. Chem. Soc. 2001, 125, 4370; q) J. F. Austin, D. W. C. MacMillan, J. Am. Chem. Soc. 2002, 124, 1172; r) S. Hanessian, V. Pham, Org. Lett. 2000, 2, 2975; s) P. Bakó, T. Bakó, A. Szöllõsy, M. Czugler, G. Keglevich, L. Tóke, Tetrahedron: Asymmetry 2002, 13, 203; t) T. Perrard, J.-C. Plaquevent, J.-R. Desmurs, D. Hebrault, Org. Lett. 2000, 2, 2959; u) F.-Y. Zhang, E. J. Corey. Org. Lett. 2000, 2, 1097; v) J. M. Betancort, K. Sakthivel, R. Thayumanavan, C. F. Barbas III, Tetrahedron Lett. 2001, 42, 4441; w) P. Melchiorre, K. A. J. Jørgensen, J. Org. Chem. 2003, 65, 4151; x) E. J. Corey, M. C. Noe, F. Xu, Tetrahedron Lett. 1998, 59, 5347.
35. For reviews on catalytic asymmetric conjugate addition reactions, see: a) M. P. Sibi, S. Manyem, Tetrahedron 2000, 56, 8033; b) N. Krause, A. Hoffmann-Röder, Synthesis 2001, 171; a) M. Yamaguchi, in: Comprehensive Asymmetric Catalysis, chapter 31.1 (Eds.: E. N. Jacobsen, A. Pfaltz, H. Yamamoto), Springer: Berlin, 1999.
36. For reviews on catalytic asymmetric conjugate addition reactions, see: a) M. P. Sibi, S. Manyem, Tetrahedron 2000, 56, 8033; b) N. Krause, A. Hoffmann-Röder, Synthesis 2001, 171; a) M. Yamaguchi, in: Comprehensive Asymmetric Catalysis, chapter 31.1 (Eds.: E. N. Jacobsen, A. Pfaltz, H. Yamamoto), Springer: Berlin, 1999.
37. For reviews on catalytic asymmetric conjugate addition reactions, see: a) M. P. Sibi, S. Manyem, Tetrahedron 2000, 56, 8033; b) N. Krause, A. Hoffmann-Röder, Synthesis 2001, 171; a) M. Yamaguchi, in: Comprehensive Asymmetric Catalysis, chapter 31.1 (Eds.: E. N. Jacobsen, A. Pfaltz, H. Yamamoto), Springer: Berlin, 1999.
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