Efficient and General Protocol for the Copper-Free Sonogashira Coupling of Aryl Bromides at Room Temperature

Organic Letters

Volumn 5, Issue 22, 2003, Pages 4191-4194

  Soheili, Arash ^a   Albaneze Walker, Jennifer ^a   Murry, Jerry A ^a   Dormer, Peter G ^a   Hughes, David L ^a  

^a MERCK RESEARCH LABORATORIES   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

BROMINE DERIVATIVE; COPPER;

ARTICLE; CATALYSIS; CHEMICAL REACTION; ROOM TEMPERATURE; SONOGASHIRA COUPLING;

EID: 0344944884     PISSN: 15237060     EISSN: None     Source Type: Journal    
DOI: 10.1021/ol035632f     Document Type: Article

References (56)

1. (a) Sonogashira, K.; Tohda, Y.; Hagihara, N. Tetrahedron Lett. 1975, 16, 4467-4470.
2. (b) Takahashi, K.; Kuroyama, Y.; Sonogashira, K.; Hagihara, N. Synthesis 1980, 627-630.
3. (c) For a general review, see: Sonogashira, K. In Metal Catalyzed Cross-Coupling Reactions; Diederich, F., Stang, P. J., Eds.; Wiley-VCH: Weinheim, 1998; Chapter 5.
4. For recent advances in Sonogashira coupling, see: (a) Hundertmark, T.; Littke, A. F.; Buchwald, S. L.; Fu, G. C. Org. Lett. 2000, 2, 1729-1731. (b) Batey, R. A.; Shen, M.; Lough, A. J. Org. Lett. 2002, 4, 1411-1414. (c) Mori, A.; Shimada, T.; Kondo, T.; Sekiguch, A. Synlett 2001, 649-651. (d) Bumagin, N. A.; Sukhomlinova, L. I.; Luzikova, E. V.; Tolstaya, T. P.; Beletsdaya, I. P. Tetrahedron Lett. 1996, 37, 897-900. (e) Radhakrishnan, U.; Stang, P. J. Org. Lett. 2001, 3, 859-860. (f) Mori, A.; Ahmed, M. S. M.; Sekiguchi, A.; Masui, K. ; Koike, T. Chem. Lett. 2002, 756-757. (g) Alammi, M.; Crousse, B.; Ferri, F. J. Organomet. Chem. 2001, 624, 114-123. (h) Crisp, G. T.; Turner, P. D.; Stephens, K. A. J. Organomet. Chem. 1998, 570, 219-224. (i) Negishi, E.; Anastasia, L. Org. Lett. 2003, 5, 1597-1600. (j) Langille, N. F.; Dakin. L. A.; Panek, J. S. Org. Lett. 2002, 4, 2485-2488. (k) Gelman, D.; Tsvelikhovsky, D.; Molander, G. A.; Blum, J. J. Org. Chem. 2002, 67, 6287-6290. (l) Yang, C.; Nolan, P. Organometallics 2002, 21, 1020-1022. (m) Kollhofer, A.; Pullmann, T.; Plenio, H. Angew. Chem., Int. Ed. Engl. 2003, 42, 1056-1057. (n) Novak, Z.; Szabo, A.; Repasi, J.; Kotschy, A. J. Org. Chem. 2003, 68, 3327-3329. (o) Elangovan, A.; Wang, Y.; Ho, T. Org. Lett. 2003, 5, 1841-1844. (p) Mori, Y.; Seki, M. J. Org. Chem. 2003, 68, 1571-1574. (q) Choudary, B. M.; Madhi, S.; Chowdari, N. S. J. Am. Chem. Soc. 2002, 124, 14127-14136. For an analogous Ni-catalyzed Sonogashira, see: (r) Beletskaya, I. P.; Latyshev, G. V.; Tsvetkov, A. V.; Lukashev, N. V. Tetrahedron Lett. 2003, 44, 5011-5013.
5. For recent advances in Sonogashira coupling, see: (a) Hundertmark, T.; Littke, A. F.; Buchwald, S. L.; Fu, G. C. Org. Lett. 2000, 2, 1729-1731. (b) Batey, R. A.; Shen, M.; Lough, A. J. Org. Lett. 2002, 4, 1411-1414. (c) Mori, A.; Shimada, T.; Kondo, T.; Sekiguch, A. Synlett 2001, 649-651. (d) Bumagin, N. A.; Sukhomlinova, L. I.; Luzikova, E. V.; Tolstaya, T. P.; Beletsdaya, I. P. Tetrahedron Lett. 1996, 37, 897-900. (e) Radhakrishnan, U.; Stang, P. J. Org. Lett. 2001, 3, 859-860. (f) Mori, A.; Ahmed, M. S. M.; Sekiguchi, A.; Masui, K. ; Koike, T. Chem. Lett. 2002, 756-757. (g) Alammi, M.; Crousse, B.; Ferri, F. J. Organomet. Chem. 2001, 624, 114-123. (h) Crisp, G. T.; Turner, P. D.; Stephens, K. A. J. Organomet. Chem. 1998, 570, 219-224. (i) Negishi, E.; Anastasia, L. Org. Lett. 2003, 5, 1597-1600. (j) Langille, N. F.; Dakin. L. A.; Panek, J. S. Org. Lett. 2002, 4, 2485-2488. (k) Gelman, D.; Tsvelikhovsky, D.; Molander, G. A.; Blum, J. J. Org. Chem. 2002, 67, 6287-6290. (l) Yang, C.; Nolan, P. Organometallics 2002, 21, 1020-1022. (m) Kollhofer, A.; Pullmann, T.; Plenio, H. Angew. Chem., Int. Ed. Engl. 2003, 42, 1056-1057. (n) Novak, Z.; Szabo, A.; Repasi, J.; Kotschy, A. J. Org. Chem. 2003, 68, 3327-3329. (o) Elangovan, A.; Wang, Y.; Ho, T. Org. Lett. 2003, 5, 1841-1844. (p) Mori, Y.; Seki, M. J. Org. Chem. 2003, 68, 1571-1574. (q) Choudary, B. M.; Madhi, S.; Chowdari, N. S. J. Am. Chem. Soc. 2002, 124, 14127-14136. For an analogous Ni-catalyzed Sonogashira, see: (r) Beletskaya, I. P.; Latyshev, G. V.; Tsvetkov, A. V.; Lukashev, N. V. Tetrahedron Lett. 2003, 44, 5011-5013.
6. For recent advances in Sonogashira coupling, see: (a) Hundertmark, T.; Littke, A. F.; Buchwald, S. L.; Fu, G. C. Org. Lett. 2000, 2, 1729-1731. (b) Batey, R. A.; Shen, M.; Lough, A. J. Org. Lett. 2002, 4, 1411-1414. (c) Mori, A.; Shimada, T.; Kondo, T.; Sekiguch, A. Synlett 2001, 649-651. (d) Bumagin, N. A.; Sukhomlinova, L. I.; Luzikova, E. V.; Tolstaya, T. P.; Beletsdaya, I. P. Tetrahedron Lett. 1996, 37, 897-900. (e) Radhakrishnan, U.; Stang, P. J. Org. Lett. 2001, 3, 859-860. (f) Mori, A.; Ahmed, M. S. M.; Sekiguchi, A.; Masui, K. ; Koike, T. Chem. Lett. 2002, 756-757. (g) Alammi, M.; Crousse, B.; Ferri, F. J. Organomet. Chem. 2001, 624, 114-123. (h) Crisp, G. T.; Turner, P. D.; Stephens, K. A. J. Organomet. Chem. 1998, 570, 219-224. (i) Negishi, E.; Anastasia, L. Org. Lett. 2003, 5, 1597-1600. (j) Langille, N. F.; Dakin. L. A.; Panek, J. S. Org. Lett. 2002, 4, 2485-2488. (k) Gelman, D.; Tsvelikhovsky, D.; Molander, G. A.; Blum, J. J. Org. Chem. 2002, 67, 6287-6290. (l) Yang, C.; Nolan, P. Organometallics 2002, 21, 1020-1022. (m) Kollhofer, A.; Pullmann, T.; Plenio, H. Angew. Chem., Int. Ed. Engl. 2003, 42, 1056-1057. (n) Novak, Z.; Szabo, A.; Repasi, J.; Kotschy, A. J. Org. Chem. 2003, 68, 3327-3329. (o) Elangovan, A.; Wang, Y.; Ho, T. Org. Lett. 2003, 5, 1841-1844. (p) Mori, Y.; Seki, M. J. Org. Chem. 2003, 68, 1571-1574. (q) Choudary, B. M.; Madhi, S.; Chowdari, N. S. J. Am. Chem. Soc. 2002, 124, 14127-14136. For an analogous Ni-catalyzed Sonogashira, see: (r) Beletskaya, I. P.; Latyshev, G. V.; Tsvetkov, A. V.; Lukashev, N. V. Tetrahedron Lett. 2003, 44, 5011-5013.
7. For recent advances in Sonogashira coupling, see: (a) Hundertmark, T.; Littke, A. F.; Buchwald, S. L.; Fu, G. C. Org. Lett. 2000, 2, 1729-1731. (b) Batey, R. A.; Shen, M.; Lough, A. J. Org. Lett. 2002, 4, 1411-1414. (c) Mori, A.; Shimada, T.; Kondo, T.; Sekiguch, A. Synlett 2001, 649-651. (d) Bumagin, N. A.; Sukhomlinova, L. I.; Luzikova, E. V.; Tolstaya, T. P.; Beletsdaya, I. P. Tetrahedron Lett. 1996, 37, 897-900. (e) Radhakrishnan, U.; Stang, P. J. Org. Lett. 2001, 3, 859-860. (f) Mori, A.; Ahmed, M. S. M.; Sekiguchi, A.; Masui, K. ; Koike, T. Chem. Lett. 2002, 756-757. (g) Alammi, M.; Crousse, B.; Ferri, F. J. Organomet. Chem. 2001, 624, 114-123. (h) Crisp, G. T.; Turner, P. D.; Stephens, K. A. J. Organomet. Chem. 1998, 570, 219-224. (i) Negishi, E.; Anastasia, L. Org. Lett. 2003, 5, 1597-1600. (j) Langille, N. F.; Dakin. L. A.; Panek, J. S. Org. Lett. 2002, 4, 2485-2488. (k) Gelman, D.; Tsvelikhovsky, D.; Molander, G. A.; Blum, J. J. Org. Chem. 2002, 67, 6287-6290. (l) Yang, C.; Nolan, P. Organometallics 2002, 21, 1020-1022. (m) Kollhofer, A.; Pullmann, T.; Plenio, H. Angew. Chem., Int. Ed. Engl. 2003, 42, 1056-1057. (n) Novak, Z.; Szabo, A.; Repasi, J.; Kotschy, A. J. Org. Chem. 2003, 68, 3327-3329. (o) Elangovan, A.; Wang, Y.; Ho, T. Org. Lett. 2003, 5, 1841-1844. (p) Mori, Y.; Seki, M. J. Org. Chem. 2003, 68, 1571-1574. (q) Choudary, B. M.; Madhi, S.; Chowdari, N. S. J. Am. Chem. Soc. 2002, 124, 14127-14136. For an analogous Ni-catalyzed Sonogashira, see: (r) Beletskaya, I. P.; Latyshev, G. V.; Tsvetkov, A. V.; Lukashev, N. V. Tetrahedron Lett. 2003, 44, 5011-5013.
8. For recent advances in Sonogashira coupling, see: (a) Hundertmark, T.; Littke, A. F.; Buchwald, S. L.; Fu, G. C. Org. Lett. 2000, 2, 1729-1731. (b) Batey, R. A.; Shen, M.; Lough, A. J. Org. Lett. 2002, 4, 1411-1414. (c) Mori, A.; Shimada, T.; Kondo, T.; Sekiguch, A. Synlett 2001, 649-651. (d) Bumagin, N. A.; Sukhomlinova, L. I.; Luzikova, E. V.; Tolstaya, T. P.; Beletsdaya, I. P. Tetrahedron Lett. 1996, 37, 897-900. (e) Radhakrishnan, U.; Stang, P. J. Org. Lett. 2001, 3, 859-860. (f) Mori, A.; Ahmed, M. S. M.; Sekiguchi, A.; Masui, K. ; Koike, T. Chem. Lett. 2002, 756-757. (g) Alammi, M.; Crousse, B.; Ferri, F. J. Organomet. Chem. 2001, 624, 114-123. (h) Crisp, G. T.; Turner, P. D.; Stephens, K. A. J. Organomet. Chem. 1998, 570, 219-224. (i) Negishi, E.; Anastasia, L. Org. Lett. 2003, 5, 1597-1600. (j) Langille, N. F.; Dakin. L. A.; Panek, J. S. Org. Lett. 2002, 4, 2485-2488. (k) Gelman, D.; Tsvelikhovsky, D.; Molander, G. A.; Blum, J. J. Org. Chem. 2002, 67, 6287-6290. (l) Yang, C.; Nolan, P. Organometallics 2002, 21, 1020-1022. (m) Kollhofer, A.; Pullmann, T.; Plenio, H. Angew. Chem., Int. Ed. Engl. 2003, 42, 1056-1057. (n) Novak, Z.; Szabo, A.; Repasi, J.; Kotschy, A. J. Org. Chem. 2003, 68, 3327-3329. (o) Elangovan, A.; Wang, Y.; Ho, T. Org. Lett. 2003, 5, 1841-1844. (p) Mori, Y.; Seki, M. J. Org. Chem. 2003, 68, 1571-1574. (q) Choudary, B. M.; Madhi, S.; Chowdari, N. S. J. Am. Chem. Soc. 2002, 124, 14127-14136. For an analogous Ni-catalyzed Sonogashira, see: (r) Beletskaya, I. P.; Latyshev, G. V.; Tsvetkov, A. V.; Lukashev, N. V. Tetrahedron Lett. 2003, 44, 5011-5013.
9. For recent advances in Sonogashira coupling, see: (a) Hundertmark, T.; Littke, A. F.; Buchwald, S. L.; Fu, G. C. Org. Lett. 2000, 2, 1729-1731. (b) Batey, R. A.; Shen, M.; Lough, A. J. Org. Lett. 2002, 4, 1411-1414. (c) Mori, A.; Shimada, T.; Kondo, T.; Sekiguch, A. Synlett 2001, 649-651. (d) Bumagin, N. A.; Sukhomlinova, L. I.; Luzikova, E. V.; Tolstaya, T. P.; Beletsdaya, I. P. Tetrahedron Lett. 1996, 37, 897-900. (e) Radhakrishnan, U.; Stang, P. J. Org. Lett. 2001, 3, 859-860. (f) Mori, A.; Ahmed, M. S. M.; Sekiguchi, A.; Masui, K. ; Koike, T. Chem. Lett. 2002, 756-757. (g) Alammi, M.; Crousse, B.; Ferri, F. J. Organomet. Chem. 2001, 624, 114-123. (h) Crisp, G. T.; Turner, P. D.; Stephens, K. A. J. Organomet. Chem. 1998, 570, 219-224. (i) Negishi, E.; Anastasia, L. Org. Lett. 2003, 5, 1597-1600. (j) Langille, N. F.; Dakin. L. A.; Panek, J. S. Org. Lett. 2002, 4, 2485-2488. (k) Gelman, D.; Tsvelikhovsky, D.; Molander, G. A.; Blum, J. J. Org. Chem. 2002, 67, 6287-6290. (l) Yang, C.; Nolan, P. Organometallics 2002, 21, 1020-1022. (m) Kollhofer, A.; Pullmann, T.; Plenio, H. Angew. Chem., Int. Ed. Engl. 2003, 42, 1056-1057. (n) Novak, Z.; Szabo, A.; Repasi, J.; Kotschy, A. J. Org. Chem. 2003, 68, 3327-3329. (o) Elangovan, A.; Wang, Y.; Ho, T. Org. Lett. 2003, 5, 1841-1844. (p) Mori, Y.; Seki, M. J. Org. Chem. 2003, 68, 1571-1574. (q) Choudary, B. M.; Madhi, S.; Chowdari, N. S. J. Am. Chem. Soc. 2002, 124, 14127-14136. For an analogous Ni-catalyzed Sonogashira, see: (r) Beletskaya, I. P.; Latyshev, G. V.; Tsvetkov, A. V.; Lukashev, N. V. Tetrahedron Lett. 2003, 44, 5011-5013.
10. For recent advances in Sonogashira coupling, see: (a) Hundertmark, T.; Littke, A. F.; Buchwald, S. L.; Fu, G. C. Org. Lett. 2000, 2, 1729-1731. (b) Batey, R. A.; Shen, M.; Lough, A. J. Org. Lett. 2002, 4, 1411-1414. (c) Mori, A.; Shimada, T.; Kondo, T.; Sekiguch, A. Synlett 2001, 649-651. (d) Bumagin, N. A.; Sukhomlinova, L. I.; Luzikova, E. V.; Tolstaya, T. P.; Beletsdaya, I. P. Tetrahedron Lett. 1996, 37, 897-900. (e) Radhakrishnan, U.; Stang, P. J. Org. Lett. 2001, 3, 859-860. (f) Mori, A.; Ahmed, M. S. M.; Sekiguchi, A.; Masui, K. ; Koike, T. Chem. Lett. 2002, 756-757. (g) Alammi, M.; Crousse, B.; Ferri, F. J. Organomet. Chem. 2001, 624, 114-123. (h) Crisp, G. T.; Turner, P. D.; Stephens, K. A. J. Organomet. Chem. 1998, 570, 219-224. (i) Negishi, E.; Anastasia, L. Org. Lett. 2003, 5, 1597-1600. (j) Langille, N. F.; Dakin. L. A.; Panek, J. S. Org. Lett. 2002, 4, 2485-2488. (k) Gelman, D.; Tsvelikhovsky, D.; Molander, G. A.; Blum, J. J. Org. Chem. 2002, 67, 6287-6290. (l) Yang, C.; Nolan, P. Organometallics 2002, 21, 1020-1022. (m) Kollhofer, A.; Pullmann, T.; Plenio, H. Angew. Chem., Int. Ed. Engl. 2003, 42, 1056-1057. (n) Novak, Z.; Szabo, A.; Repasi, J.; Kotschy, A. J. Org. Chem. 2003, 68, 3327-3329. (o) Elangovan, A.; Wang, Y.; Ho, T. Org. Lett. 2003, 5, 1841-1844. (p) Mori, Y.; Seki, M. J. Org. Chem. 2003, 68, 1571-1574. (q) Choudary, B. M.; Madhi, S.; Chowdari, N. S. J. Am. Chem. Soc. 2002, 124, 14127-14136. For an analogous Ni-catalyzed Sonogashira, see: (r) Beletskaya, I. P.; Latyshev, G. V.; Tsvetkov, A. V.; Lukashev, N. V. Tetrahedron Lett. 2003, 44, 5011-5013.
11. For recent advances in Sonogashira coupling, see: (a) Hundertmark, T.; Littke, A. F.; Buchwald, S. L.; Fu, G. C. Org. Lett. 2000, 2, 1729-1731. (b) Batey, R. A.; Shen, M.; Lough, A. J. Org. Lett. 2002, 4, 1411-1414. (c) Mori, A.; Shimada, T.; Kondo, T.; Sekiguch, A. Synlett 2001, 649-651. (d) Bumagin, N. A.; Sukhomlinova, L. I.; Luzikova, E. V.; Tolstaya, T. P.; Beletsdaya, I. P. Tetrahedron Lett. 1996, 37, 897-900. (e) Radhakrishnan, U.; Stang, P. J. Org. Lett. 2001, 3, 859-860. (f) Mori, A.; Ahmed, M. S. M.; Sekiguchi, A.; Masui, K. ; Koike, T. Chem. Lett. 2002, 756-757. (g) Alammi, M.; Crousse, B.; Ferri, F. J. Organomet. Chem. 2001, 624, 114-123. (h) Crisp, G. T.; Turner, P. D.; Stephens, K. A. J. Organomet. Chem. 1998, 570, 219-224. (i) Negishi, E.; Anastasia, L. Org. Lett. 2003, 5, 1597-1600. (j) Langille, N. F.; Dakin. L. A.; Panek, J. S. Org. Lett. 2002, 4, 2485-2488. (k) Gelman, D.; Tsvelikhovsky, D.; Molander, G. A.; Blum, J. J. Org. Chem. 2002, 67, 6287-6290. (l) Yang, C.; Nolan, P. Organometallics 2002, 21, 1020-1022. (m) Kollhofer, A.; Pullmann, T.; Plenio, H. Angew. Chem., Int. Ed. Engl. 2003, 42, 1056-1057. (n) Novak, Z.; Szabo, A.; Repasi, J.; Kotschy, A. J. Org. Chem. 2003, 68, 3327-3329. (o) Elangovan, A.; Wang, Y.; Ho, T. Org. Lett. 2003, 5, 1841-1844. (p) Mori, Y.; Seki, M. J. Org. Chem. 2003, 68, 1571-1574. (q) Choudary, B. M.; Madhi, S.; Chowdari, N. S. J. Am. Chem. Soc. 2002, 124, 14127-14136. For an analogous Ni-catalyzed Sonogashira, see: (r) Beletskaya, I. P.; Latyshev, G. V.; Tsvetkov, A. V.; Lukashev, N. V. Tetrahedron Lett. 2003, 44, 5011-5013.
12. For recent advances in Sonogashira coupling, see: (a) Hundertmark, T.; Littke, A. F.; Buchwald, S. L.; Fu, G. C. Org. Lett. 2000, 2, 1729-1731. (b) Batey, R. A.; Shen, M.; Lough, A. J. Org. Lett. 2002, 4, 1411-1414. (c) Mori, A.; Shimada, T.; Kondo, T.; Sekiguch, A. Synlett 2001, 649-651. (d) Bumagin, N. A.; Sukhomlinova, L. I.; Luzikova, E. V.; Tolstaya, T. P.; Beletsdaya, I. P. Tetrahedron Lett. 1996, 37, 897-900. (e) Radhakrishnan, U.; Stang, P. J. Org. Lett. 2001, 3, 859-860. (f) Mori, A.; Ahmed, M. S. M.; Sekiguchi, A.; Masui, K. ; Koike, T. Chem. Lett. 2002, 756-757. (g) Alammi, M.; Crousse, B.; Ferri, F. J. Organomet. Chem. 2001, 624, 114-123. (h) Crisp, G. T.; Turner, P. D.; Stephens, K. A. J. Organomet. Chem. 1998, 570, 219-224. (i) Negishi, E.; Anastasia, L. Org. Lett. 2003, 5, 1597-1600. (j) Langille, N. F.; Dakin. L. A.; Panek, J. S. Org. Lett. 2002, 4, 2485-2488. (k) Gelman, D.; Tsvelikhovsky, D.; Molander, G. A.; Blum, J. J. Org. Chem. 2002, 67, 6287-6290. (l) Yang, C.; Nolan, P. Organometallics 2002, 21, 1020-1022. (m) Kollhofer, A.; Pullmann, T.; Plenio, H. Angew. Chem., Int. Ed. Engl. 2003, 42, 1056-1057. (n) Novak, Z.; Szabo, A.; Repasi, J.; Kotschy, A. J. Org. Chem. 2003, 68, 3327-3329. (o) Elangovan, A.; Wang, Y.; Ho, T. Org. Lett. 2003, 5, 1841-1844. (p) Mori, Y.; Seki, M. J. Org. Chem. 2003, 68, 1571-1574. (q) Choudary, B. M.; Madhi, S.; Chowdari, N. S. J. Am. Chem. Soc. 2002, 124, 14127-14136. For an analogous Ni-catalyzed Sonogashira, see: (r) Beletskaya, I. P.; Latyshev, G. V.; Tsvetkov, A. V.; Lukashev, N. V. Tetrahedron Lett. 2003, 44, 5011-5013.
13. For recent advances in Sonogashira coupling, see: (a) Hundertmark, T.; Littke, A. F.; Buchwald, S. L.; Fu, G. C. Org. Lett. 2000, 2, 1729-1731. (b) Batey, R. A.; Shen, M.; Lough, A. J. Org. Lett. 2002, 4, 1411-1414. (c) Mori, A.; Shimada, T.; Kondo, T.; Sekiguch, A. Synlett 2001, 649-651. (d) Bumagin, N. A.; Sukhomlinova, L. I.; Luzikova, E. V.; Tolstaya, T. P.; Beletsdaya, I. P. Tetrahedron Lett. 1996, 37, 897-900. (e) Radhakrishnan, U.; Stang, P. J. Org. Lett. 2001, 3, 859-860. (f) Mori, A.; Ahmed, M. S. M.; Sekiguchi, A.; Masui, K. ; Koike, T. Chem. Lett. 2002, 756-757. (g) Alammi, M.; Crousse, B.; Ferri, F. J. Organomet. Chem. 2001, 624, 114-123. (h) Crisp, G. T.; Turner, P. D.; Stephens, K. A. J. Organomet. Chem. 1998, 570, 219-224. (i) Negishi, E.; Anastasia, L. Org. Lett. 2003, 5, 1597-1600. (j) Langille, N. F.; Dakin. L. A.; Panek, J. S. Org. Lett. 2002, 4, 2485-2488. (k) Gelman, D.; Tsvelikhovsky, D.; Molander, G. A.; Blum, J. J. Org. Chem. 2002, 67, 6287-6290. (l) Yang, C.; Nolan, P. Organometallics 2002, 21, 1020-1022. (m) Kollhofer, A.; Pullmann, T.; Plenio, H. Angew. Chem., Int. Ed. Engl. 2003, 42, 1056-1057. (n) Novak, Z.; Szabo, A.; Repasi, J.; Kotschy, A. J. Org. Chem. 2003, 68, 3327-3329. (o) Elangovan, A.; Wang, Y.; Ho, T. Org. Lett. 2003, 5, 1841-1844. (p) Mori, Y.; Seki, M. J. Org. Chem. 2003, 68, 1571-1574. (q) Choudary, B. M.; Madhi, S.; Chowdari, N. S. J. Am. Chem. Soc. 2002, 124, 14127-14136. For an analogous Ni-catalyzed Sonogashira, see: (r) Beletskaya, I. P.; Latyshev, G. V.; Tsvetkov, A. V.; Lukashev, N. V. Tetrahedron Lett. 2003, 44, 5011-5013.
14. For recent advances in Sonogashira coupling, see: (a) Hundertmark, T.; Littke, A. F.; Buchwald, S. L.; Fu, G. C. Org. Lett. 2000, 2, 1729-1731. (b) Batey, R. A.; Shen, M.; Lough, A. J. Org. Lett. 2002, 4, 1411-1414. (c) Mori, A.; Shimada, T.; Kondo, T.; Sekiguch, A. Synlett 2001, 649-651. (d) Bumagin, N. A.; Sukhomlinova, L. I.; Luzikova, E. V.; Tolstaya, T. P.; Beletsdaya, I. P. Tetrahedron Lett. 1996, 37, 897-900. (e) Radhakrishnan, U.; Stang, P. J. Org. Lett. 2001, 3, 859-860. (f) Mori, A.; Ahmed, M. S. M.; Sekiguchi, A.; Masui, K. ; Koike, T. Chem. Lett. 2002, 756-757. (g) Alammi, M.; Crousse, B.; Ferri, F. J. Organomet. Chem. 2001, 624, 114-123. (h) Crisp, G. T.; Turner, P. D.; Stephens, K. A. J. Organomet. Chem. 1998, 570, 219-224. (i) Negishi, E.; Anastasia, L. Org. Lett. 2003, 5, 1597-1600. (j) Langille, N. F.; Dakin. L. A.; Panek, J. S. Org. Lett. 2002, 4, 2485-2488. (k) Gelman, D.; Tsvelikhovsky, D.; Molander, G. A.; Blum, J. J. Org. Chem. 2002, 67, 6287-6290. (l) Yang, C.; Nolan, P. Organometallics 2002, 21, 1020-1022. (m) Kollhofer, A.; Pullmann, T.; Plenio, H. Angew. Chem., Int. Ed. Engl. 2003, 42, 1056-1057. (n) Novak, Z.; Szabo, A.; Repasi, J.; Kotschy, A. J. Org. Chem. 2003, 68, 3327-3329. (o) Elangovan, A.; Wang, Y.; Ho, T. Org. Lett. 2003, 5, 1841-1844. (p) Mori, Y.; Seki, M. J. Org. Chem. 2003, 68, 1571-1574. (q) Choudary, B. M.; Madhi, S.; Chowdari, N. S. J. Am. Chem. Soc. 2002, 124, 14127-14136. For an analogous Ni-catalyzed Sonogashira, see: (r) Beletskaya, I. P.; Latyshev, G. V.; Tsvetkov, A. V.; Lukashev, N. V. Tetrahedron Lett. 2003, 44, 5011-5013.
15. For recent advances in Sonogashira coupling, see: (a) Hundertmark, T.; Littke, A. F.; Buchwald, S. L.; Fu, G. C. Org. Lett. 2000, 2, 1729-1731. (b) Batey, R. A.; Shen, M.; Lough, A. J. Org. Lett. 2002, 4, 1411-1414. (c) Mori, A.; Shimada, T.; Kondo, T.; Sekiguch, A. Synlett 2001, 649-651. (d) Bumagin, N. A.; Sukhomlinova, L. I.; Luzikova, E. V.; Tolstaya, T. P.; Beletsdaya, I. P. Tetrahedron Lett. 1996, 37, 897-900. (e) Radhakrishnan, U.; Stang, P. J. Org. Lett. 2001, 3, 859-860. (f) Mori, A.; Ahmed, M. S. M.; Sekiguchi, A.; Masui, K. ; Koike, T. Chem. Lett. 2002, 756-757. (g) Alammi, M.; Crousse, B.; Ferri, F. J. Organomet. Chem. 2001, 624, 114-123. (h) Crisp, G. T.; Turner, P. D.; Stephens, K. A. J. Organomet. Chem. 1998, 570, 219-224. (i) Negishi, E.; Anastasia, L. Org. Lett. 2003, 5, 1597-1600. (j) Langille, N. F.; Dakin. L. A.; Panek, J. S. Org. Lett. 2002, 4, 2485-2488. (k) Gelman, D.; Tsvelikhovsky, D.; Molander, G. A.; Blum, J. J. Org. Chem. 2002, 67, 6287-6290. (l) Yang, C.; Nolan, P. Organometallics 2002, 21, 1020-1022. (m) Kollhofer, A.; Pullmann, T.; Plenio, H. Angew. Chem., Int. Ed. Engl. 2003, 42, 1056-1057. (n) Novak, Z.; Szabo, A.; Repasi, J.; Kotschy, A. J. Org. Chem. 2003, 68, 3327-3329. (o) Elangovan, A.; Wang, Y.; Ho, T. Org. Lett. 2003, 5, 1841-1844. (p) Mori, Y.; Seki, M. J. Org. Chem. 2003, 68, 1571-1574. (q) Choudary, B. M.; Madhi, S.; Chowdari, N. S. J. Am. Chem. Soc. 2002, 124, 14127-14136. For an analogous Ni-catalyzed Sonogashira, see: (r) Beletskaya, I. P.; Latyshev, G. V.; Tsvetkov, A. V.; Lukashev, N. V. Tetrahedron Lett. 2003, 44, 5011-5013.
16. For recent advances in Sonogashira coupling, see: (a) Hundertmark, T.; Littke, A. F.; Buchwald, S. L.; Fu, G. C. Org. Lett. 2000, 2, 1729-1731. (b) Batey, R. A.; Shen, M.; Lough, A. J. Org. Lett. 2002, 4, 1411-1414. (c) Mori, A.; Shimada, T.; Kondo, T.; Sekiguch, A. Synlett 2001, 649-651. (d) Bumagin, N. A.; Sukhomlinova, L. I.; Luzikova, E. V.; Tolstaya, T. P.; Beletsdaya, I. P. Tetrahedron Lett. 1996, 37, 897-900. (e) Radhakrishnan, U.; Stang, P. J. Org. Lett. 2001, 3, 859-860. (f) Mori, A.; Ahmed, M. S. M.; Sekiguchi, A.; Masui, K. ; Koike, T. Chem. Lett. 2002, 756-757. (g) Alammi, M.; Crousse, B.; Ferri, F. J. Organomet. Chem. 2001, 624, 114-123. (h) Crisp, G. T.; Turner, P. D.; Stephens, K. A. J. Organomet. Chem. 1998, 570, 219-224. (i) Negishi, E.; Anastasia, L. Org. Lett. 2003, 5, 1597-1600. (j) Langille, N. F.; Dakin. L. A.; Panek, J. S. Org. Lett. 2002, 4, 2485-2488. (k) Gelman, D.; Tsvelikhovsky, D.; Molander, G. A.; Blum, J. J. Org. Chem. 2002, 67, 6287-6290. (l) Yang, C.; Nolan, P. Organometallics 2002, 21, 1020-1022. (m) Kollhofer, A.; Pullmann, T.; Plenio, H. Angew. Chem., Int. Ed. Engl. 2003, 42, 1056-1057. (n) Novak, Z.; Szabo, A.; Repasi, J.; Kotschy, A. J. Org. Chem. 2003, 68, 3327-3329. (o) Elangovan, A.; Wang, Y.; Ho, T. Org. Lett. 2003, 5, 1841-1844. (p) Mori, Y.; Seki, M. J. Org. Chem. 2003, 68, 1571-1574. (q) Choudary, B. M.; Madhi, S.; Chowdari, N. S. J. Am. Chem. Soc. 2002, 124, 14127-14136. For an analogous Ni-catalyzed Sonogashira, see: (r) Beletskaya, I. P.; Latyshev, G. V.; Tsvetkov, A. V.; Lukashev, N. V. Tetrahedron Lett. 2003, 44, 5011-5013.
17. For recent advances in Sonogashira coupling, see: (a) Hundertmark, T.; Littke, A. F.; Buchwald, S. L.; Fu, G. C. Org. Lett. 2000, 2, 1729-1731. (b) Batey, R. A.; Shen, M.; Lough, A. J. Org. Lett. 2002, 4, 1411-1414. (c) Mori, A.; Shimada, T.; Kondo, T.; Sekiguch, A. Synlett 2001, 649-651. (d) Bumagin, N. A.; Sukhomlinova, L. I.; Luzikova, E. V.; Tolstaya, T. P.; Beletsdaya, I. P. Tetrahedron Lett. 1996, 37, 897-900. (e) Radhakrishnan, U.; Stang, P. J. Org. Lett. 2001, 3, 859-860. (f) Mori, A.; Ahmed, M. S. M.; Sekiguchi, A.; Masui, K. ; Koike, T. Chem. Lett. 2002, 756-757. (g) Alammi, M.; Crousse, B.; Ferri, F. J. Organomet. Chem. 2001, 624, 114-123. (h) Crisp, G. T.; Turner, P. D.; Stephens, K. A. J. Organomet. Chem. 1998, 570, 219-224. (i) Negishi, E.; Anastasia, L. Org. Lett. 2003, 5, 1597-1600. (j) Langille, N. F.; Dakin. L. A.; Panek, J. S. Org. Lett. 2002, 4, 2485-2488. (k) Gelman, D.; Tsvelikhovsky, D.; Molander, G. A.; Blum, J. J. Org. Chem. 2002, 67, 6287-6290. (l) Yang, C.; Nolan, P. Organometallics 2002, 21, 1020-1022. (m) Kollhofer, A.; Pullmann, T.; Plenio, H. Angew. Chem., Int. Ed. Engl. 2003, 42, 1056-1057. (n) Novak, Z.; Szabo, A.; Repasi, J.; Kotschy, A. J. Org. Chem. 2003, 68, 3327-3329. (o) Elangovan, A.; Wang, Y.; Ho, T. Org. Lett. 2003, 5, 1841-1844. (p) Mori, Y.; Seki, M. J. Org. Chem. 2003, 68, 1571-1574. (q) Choudary, B. M.; Madhi, S.; Chowdari, N. S. J. Am. Chem. Soc. 2002, 124, 14127-14136. For an analogous Ni-catalyzed Sonogashira, see: (r) Beletskaya, I. P.; Latyshev, G. V.; Tsvetkov, A. V.; Lukashev, N. V. Tetrahedron Lett. 2003, 44, 5011-5013.
18. For recent advances in Sonogashira coupling, see: (a) Hundertmark, T.; Littke, A. F.; Buchwald, S. L.; Fu, G. C. Org. Lett. 2000, 2, 1729-1731. (b) Batey, R. A.; Shen, M.; Lough, A. J. Org. Lett. 2002, 4, 1411-1414. (c) Mori, A.; Shimada, T.; Kondo, T.; Sekiguch, A. Synlett 2001, 649-651. (d) Bumagin, N. A.; Sukhomlinova, L. I.; Luzikova, E. V.; Tolstaya, T. P.; Beletsdaya, I. P. Tetrahedron Lett. 1996, 37, 897-900. (e) Radhakrishnan, U.; Stang, P. J. Org. Lett. 2001, 3, 859-860. (f) Mori, A.; Ahmed, M. S. M.; Sekiguchi, A.; Masui, K. ; Koike, T. Chem. Lett. 2002, 756-757. (g) Alammi, M.; Crousse, B.; Ferri, F. J. Organomet. Chem. 2001, 624, 114-123. (h) Crisp, G. T.; Turner, P. D.; Stephens, K. A. J. Organomet. Chem. 1998, 570, 219-224. (i) Negishi, E.; Anastasia, L. Org. Lett. 2003, 5, 1597-1600. (j) Langille, N. F.; Dakin. L. A.; Panek, J. S. Org. Lett. 2002, 4, 2485-2488. (k) Gelman, D.; Tsvelikhovsky, D.; Molander, G. A.; Blum, J. J. Org. Chem. 2002, 67, 6287-6290. (l) Yang, C.; Nolan, P. Organometallics 2002, 21, 1020-1022. (m) Kollhofer, A.; Pullmann, T.; Plenio, H. Angew. Chem., Int. Ed. Engl. 2003, 42, 1056-1057. (n) Novak, Z.; Szabo, A.; Repasi, J.; Kotschy, A. J. Org. Chem. 2003, 68, 3327-3329. (o) Elangovan, A.; Wang, Y.; Ho, T. Org. Lett. 2003, 5, 1841-1844. (p) Mori, Y.; Seki, M. J. Org. Chem. 2003, 68, 1571-1574. (q) Choudary, B. M.; Madhi, S.; Chowdari, N. S. J. Am. Chem. Soc. 2002, 124, 14127-14136. For an analogous Ni-catalyzed Sonogashira, see: (r) Beletskaya, I. P.; Latyshev, G. V.; Tsvetkov, A. V.; Lukashev, N. V. Tetrahedron Lett. 2003, 44, 5011-5013.
19. For recent advances in Sonogashira coupling, see: (a) Hundertmark, T.; Littke, A. F.; Buchwald, S. L.; Fu, G. C. Org. Lett. 2000, 2, 1729-1731. (b) Batey, R. A.; Shen, M.; Lough, A. J. Org. Lett. 2002, 4, 1411-1414. (c) Mori, A.; Shimada, T.; Kondo, T.; Sekiguch, A. Synlett 2001, 649-651. (d) Bumagin, N. A.; Sukhomlinova, L. I.; Luzikova, E. V.; Tolstaya, T. P.; Beletsdaya, I. P. Tetrahedron Lett. 1996, 37, 897-900. (e) Radhakrishnan, U.; Stang, P. J. Org. Lett. 2001, 3, 859-860. (f) Mori, A.; Ahmed, M. S. M.; Sekiguchi, A.; Masui, K. ; Koike, T. Chem. Lett. 2002, 756-757. (g) Alammi, M.; Crousse, B.; Ferri, F. J. Organomet. Chem. 2001, 624, 114-123. (h) Crisp, G. T.; Turner, P. D.; Stephens, K. A. J. Organomet. Chem. 1998, 570, 219-224. (i) Negishi, E.; Anastasia, L. Org. Lett. 2003, 5, 1597-1600. (j) Langille, N. F.; Dakin. L. A.; Panek, J. S. Org. Lett. 2002, 4, 2485-2488. (k) Gelman, D.; Tsvelikhovsky, D.; Molander, G. A.; Blum, J. J. Org. Chem. 2002, 67, 6287-6290. (l) Yang, C.; Nolan, P. Organometallics 2002, 21, 1020-1022. (m) Kollhofer, A.; Pullmann, T.; Plenio, H. Angew. Chem., Int. Ed. Engl. 2003, 42, 1056-1057. (n) Novak, Z.; Szabo, A.; Repasi, J.; Kotschy, A. J. Org. Chem. 2003, 68, 3327-3329. (o) Elangovan, A.; Wang, Y.; Ho, T. Org. Lett. 2003, 5, 1841-1844. (p) Mori, Y.; Seki, M. J. Org. Chem. 2003, 68, 1571-1574. (q) Choudary, B. M.; Madhi, S.; Chowdari, N. S. J. Am. Chem. Soc. 2002, 124, 14127-14136. For an analogous Ni-catalyzed Sonogashira, see: (r) Beletskaya, I. P.; Latyshev, G. V.; Tsvetkov, A. V.; Lukashev, N. V. Tetrahedron Lett. 2003, 44, 5011-5013.
20. For recent advances in Sonogashira coupling, see: (a) Hundertmark, T.; Littke, A. F.; Buchwald, S. L.; Fu, G. C. Org. Lett. 2000, 2, 1729-1731. (b) Batey, R. A.; Shen, M.; Lough, A. J. Org. Lett. 2002, 4, 1411-1414. (c) Mori, A.; Shimada, T.; Kondo, T.; Sekiguch, A. Synlett 2001, 649-651. (d) Bumagin, N. A.; Sukhomlinova, L. I.; Luzikova, E. V.; Tolstaya, T. P.; Beletsdaya, I. P. Tetrahedron Lett. 1996, 37, 897-900. (e) Radhakrishnan, U.; Stang, P. J. Org. Lett. 2001, 3, 859-860. (f) Mori, A.; Ahmed, M. S. M.; Sekiguchi, A.; Masui, K. ; Koike, T. Chem. Lett. 2002, 756-757. (g) Alammi, M.; Crousse, B.; Ferri, F. J. Organomet. Chem. 2001, 624, 114-123. (h) Crisp, G. T.; Turner, P. D.; Stephens, K. A. J. Organomet. Chem. 1998, 570, 219-224. (i) Negishi, E.; Anastasia, L. Org. Lett. 2003, 5, 1597-1600. (j) Langille, N. F.; Dakin. L. A.; Panek, J. S. Org. Lett. 2002, 4, 2485-2488. (k) Gelman, D.; Tsvelikhovsky, D.; Molander, G. A.; Blum, J. J. Org. Chem. 2002, 67, 6287-6290. (l) Yang, C.; Nolan, P. Organometallics 2002, 21, 1020-1022. (m) Kollhofer, A.; Pullmann, T.; Plenio, H. Angew. Chem., Int. Ed. Engl. 2003, 42, 1056-1057. (n) Novak, Z.; Szabo, A.; Repasi, J.; Kotschy, A. J. Org. Chem. 2003, 68, 3327-3329. (o) Elangovan, A.; Wang, Y.; Ho, T. Org. Lett. 2003, 5, 1841-1844. (p) Mori, Y.; Seki, M. J. Org. Chem. 2003, 68, 1571-1574. (q) Choudary, B. M.; Madhi, S.; Chowdari, N. S. J. Am. Chem. Soc. 2002, 124, 14127-14136. For an analogous Ni-catalyzed Sonogashira, see: (r) Beletskaya, I. P.; Latyshev, G. V.; Tsvetkov, A. V.; Lukashev, N. V. Tetrahedron Lett. 2003, 44, 5011-5013.
21. For recent advances in Sonogashira coupling, see: (a) Hundertmark, T.; Littke, A. F.; Buchwald, S. L.; Fu, G. C. Org. Lett. 2000, 2, 1729-1731. (b) Batey, R. A.; Shen, M.; Lough, A. J. Org. Lett. 2002, 4, 1411-1414. (c) Mori, A.; Shimada, T.; Kondo, T.; Sekiguch, A. Synlett 2001, 649-651. (d) Bumagin, N. A.; Sukhomlinova, L. I.; Luzikova, E. V.; Tolstaya, T. P.; Beletsdaya, I. P. Tetrahedron Lett. 1996, 37, 897-900. (e) Radhakrishnan, U.; Stang, P. J. Org. Lett. 2001, 3, 859-860. (f) Mori, A.; Ahmed, M. S. M.; Sekiguchi, A.; Masui, K. ; Koike, T. Chem. Lett. 2002, 756-757. (g) Alammi, M.; Crousse, B.; Ferri, F. J. Organomet. Chem. 2001, 624, 114-123. (h) Crisp, G. T.; Turner, P. D.; Stephens, K. A. J. Organomet. Chem. 1998, 570, 219-224. (i) Negishi, E.; Anastasia, L. Org. Lett. 2003, 5, 1597-1600. (j) Langille, N. F.; Dakin. L. A.; Panek, J. S. Org. Lett. 2002, 4, 2485-2488. (k) Gelman, D.; Tsvelikhovsky, D.; Molander, G. A.; Blum, J. J. Org. Chem. 2002, 67, 6287-6290. (l) Yang, C.; Nolan, P. Organometallics 2002, 21, 1020-1022. (m) Kollhofer, A.; Pullmann, T.; Plenio, H. Angew. Chem., Int. Ed. Engl. 2003, 42, 1056-1057. (n) Novak, Z.; Szabo, A.; Repasi, J.; Kotschy, A. J. Org. Chem. 2003, 68, 3327-3329. (o) Elangovan, A.; Wang, Y.; Ho, T. Org. Lett. 2003, 5, 1841-1844. (p) Mori, Y.; Seki, M. J. Org. Chem. 2003, 68, 1571-1574. (q) Choudary, B. M.; Madhi, S.; Chowdari, N. S. J. Am. Chem. Soc. 2002, 124, 14127-14136. For an analogous Ni-catalyzed Sonogashira, see: (r) Beletskaya, I. P.; Latyshev, G. V.; Tsvetkov, A. V.; Lukashev, N. V. Tetrahedron Lett. 2003, 44, 5011-5013.
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38. (i) Ma, Y.; Song, C.; Jiang, W.; Wu, Q.; Wang, Y.; Liu, X.; Andrus, M. B. Org. Lett. 2003, ASAP.
39. 2 in palladium cross-coupling reactions, see: (a) Littke, A. F.; Schwarz, L.; Fu, G. C. J. Am. Chem. Soc. 2002, 124, 6343-6348. (b) Netherton, M. R.; Fu, G. C. Org. Lett. 2001, 3. 4295-4298. (c) Dai, C.; Fu, G. C. J. Am. Chem. Soc. 2001, 123, 2719-2724. (d) Littke, A. F.; Dai, C.; Fu, G. C. J. Am. Chem. Soc. 2000, 122, 4020-4028.
40. 2 in palladium cross-coupling reactions, see: (a) Littke, A. F.; Schwarz, L.; Fu, G. C. J. Am. Chem. Soc. 2002, 124, 6343-6348. (b) Netherton, M. R.; Fu, G. C. Org. Lett. 2001, 3. 4295-4298. (c) Dai, C.; Fu, G. C. J. Am. Chem. Soc. 2001, 123, 2719-2724. (d) Littke, A. F.; Dai, C.; Fu, G. C. J. Am. Chem. Soc. 2000, 122, 4020-4028.
41. 2 in palladium cross-coupling reactions, see: (a) Littke, A. F.; Schwarz, L.; Fu, G. C. J. Am. Chem. Soc. 2002, 124, 6343-6348. (b) Netherton, M. R.; Fu, G. C. Org. Lett. 2001, 3. 4295-4298. (c) Dai, C.; Fu, G. C. J. Am. Chem. Soc. 2001, 123, 2719-2724. (d) Littke, A. F.; Dai, C.; Fu, G. C. J. Am. Chem. Soc. 2000, 122, 4020-4028.
42. 2 in palladium cross-coupling reactions, see: (a) Littke, A. F.; Schwarz, L.; Fu, G. C. J. Am. Chem. Soc. 2002, 124, 6343-6348. (b) Netherton, M. R.; Fu, G. C. Org. Lett. 2001, 3. 4295-4298. (c) Dai, C.; Fu, G. C. J. Am. Chem. Soc. 2001, 123, 2719-2724. (d) Littke, A. F.; Dai, C.; Fu, G. C. J. Am. Chem. Soc. 2000, 122, 4020-4028.
43. Gray/brown discoloration of catalyst over time was observed when stored in the glovebox or in the freezer.
44. 13C NMR revealed only poorly resolved polymeric material.
45. Due to convenient workup, we chose acetonitrile in preference to DMF to continue our investigation.
46. 3 (0.64 mL of a 10 wt % solution in hexanes, 0.21 mmol), phenylacetylene (0.26 mL, 2.33 mmol), and piperidine (0.42 mL, 4.24 mmol) were added in that order via a syringe to the stirred reaction mixture. During the reaction, the precipitation of piperidine bromide salt was observed. After completion of reaction, as determined by complete HPLC consumption of aryl halide, EtOAc (10 mL) and water (5 mL) were added to the reaction mixture. The layers were separated, and the aqueous layer was extracted with 2 × 10 mL of EtOAc. The organic layers were combined and then washed with brine, dried with sodium sulfate, and concentrated. Purification by flash chromatography (95:5 hexanes/EtOAc) furnished the desired product (0.46 g, 92%) as a solid.
47. Prolonged reaction times (2 days) and incomplete conversion (∼90%) was observed when using piperidine as the base.
48. For mechanism of the copper-catalyzed Sonogashira coupling, see: (a) Osakada, K.; Sakata, R.; Yamamoto, T. Organometallics 1997, 16, 5354-5364. (b) Espinet, P.; Fornies, J.; Martinez, F.; Sotes, M.; Lalinde, E.; Moreno, M. T.; Ruiz, A.; Welch, A. J. J. Organomet. Chem. 1991, 403, 253-267.
49. For mechanism of the copper-catalyzed Sonogashira coupling, see: (a) Osakada, K.; Sakata, R.; Yamamoto, T. Organometallics 1997, 16, 5354-5364. (b) Espinet, P.; Fornies, J.; Martinez, F.; Sotes, M.; Lalinde, E.; Moreno, M. T.; Ruiz, A.; Welch, A. J. J. Organomet. Chem. 1991, 403, 253-267.
50. Denmark, S. E.; Wu, Z. Org. Lett. 1999, 1, 1495-1498.
51. 3CN (0.6 mL). The solution immediately turned yellow with the precipitation of a white solid. The NMR tube was then sealed and removed from the glovebox.
52. 2 is not soluble in acetonitrile or DMF but has high solubility in toluene and benzene.
53. 3 react in acetonitrile to make allylphosphonium chloride only at elevated temperatures. No reaction is observed at room temperature. This suggests that the formation of allylphosphonium chloride in the reaction comes from a π-allyl Pd species that is more activated for nucleophilic attack by the phosphine.
54. Pd-L species has been rationalized by Fu, Hartwig, Buchwald, and others as the active species in many coupling reactions.
55. See Supporting Information for full details.
56. Roy, A. H.; Hartwig, J. F. J. Am. Chem. Soc. 2001, 123, 1232-1233.