Diastereoselective 6-exo radical cyclizations of oxime ethers: Total synthesis of 7-deoxypancratistatin

Journal of Organic Chemistry

Volumn 64, Issue 12, 1999, Pages 4465-4476

  Keck, Gary E ^a   McHardy, Stanton F ^a   Murry, Jerry A ^a  

^a UNIVERSITY OF UTAH   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

7 DEOXYPANCRATISTATIN; ETHER DERIVATIVE; OXIME DERIVATIVE; UNCLASSIFIED DRUG;

ANTINEOPLASTIC ACTIVITY; ANTIVIRAL ACTIVITY; ARTICLE; CHEMICAL REACTION; CYCLIZATION; DIASTEREOISOMER; DRUG ACTIVITY; DRUG STRUCTURE; DRUG SYNTHESIS; REACTION ANALYSIS; STEREOCHEMISTRY;

EID: 0033546379     PISSN: 00223263     EISSN: None     Source Type: Journal    
DOI: 10.1021/jo9902042     Document Type: Article

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23. For previous work on both inter- and intramolecular free radical additions to oxime ethers, see: (a) Chiara, J. L.; Marco-Contelles, J.; Khair, N.; Gallego, P.; Destabel, C.; Bernabe, M. J. Org. Chem. 1995, 60, 6010. (b) Kiguchi, T.; Tajiri, K.; Ninomiya, I.; Naito, T. Tetrahedron Lett. 1995, 36, 253. (c) Naito, T.; Tajiri, K.; Harimoto, T.; Ninomiya, I.; Kiguchi, T. Tetrahedron Lett. 1994, 35, 2205. (d) Booth, S. E.; Jenkins, P. R.; Swain, C. J.; Sweeney, J. B.; J. Chem. Soc., Perkin Trans. 1 1994, 3499. (e) Parker, K.; Fokas, D. J. Org. Chem. 1994, 59, 3927. (f) Grissom, J. W.; Klingberg, D. J. Org. Chem. 1993, 58, 6559. (g) Pattenden, G.; Schulz, D. J. Tetrahedron Lett. 1993, 34, 6787. (h) Hatem, J.; Henriet-Bernard, C.; Grimaldi, J.; Maurin, R. Tetrahedron Lett. 1992, 33, 1057. (i) Marco-Contelles, J.; Pozuelo, C.; Jimeno, M. L.; Martinez, L.; Martinez-Grau, A. J. Org. Chem. 1992, 57, 2625. (j) Marco-Contelles, J.; Ruiz, P.; Sanchez, B.; Jimeno, M. L. Tetrahedron Lett. 1992, 33, 5261. (k) Parker, K. A.; Fokas, D. J. Am. Chem. Soc. 1992, 114, 9688. (l) Marco-Contelles, J.; Martinez, L.; Martinez-Grau, A.; Pozuelo, C.; Jimeno, M. L. Tetrahedron Lett. 1991, 32, 6437. (m) Booth, S. E.; Jenkins, P. R.; Swain, C. J. J. Chem. Soc., Chem. Commun. 1991, 1248. (n) Marco-Contelles, J.; Martinez, L.; Martinez- Grau, A. Tetrahedron: Asymmetry 1991, 2, 961. (o) Enholm, E. J.; Burnoff, J. A.; Jaramillo, L. M. Tetrahedron Lett. 1990, 31, 3727. (p) Parker, K. A.; Spero, D. M.; Van Epp, J. J. Org. Chem. 1988, 53, 4628. (q) Bartlett, P. A.; McLaren, K. L.; Ting, P. C. J. Am. Chem. Soc. 1988, 110, 1633. (r) Hart, D. J.; Seely, F. J. Am. Chem. Soc. 1988, 110, 1631. (s) Corey, E. J.; Pyne, S. G. Tetrahedron Lett. 1983, 24, 2821.
24. For previous work on both inter- and intramolecular free radical additions to oxime ethers, see: (a) Chiara, J. L.; Marco-Contelles, J.; Khair, N.; Gallego, P.; Destabel, C.; Bernabe, M. J. Org. Chem. 1995, 60, 6010. (b) Kiguchi, T.; Tajiri, K.; Ninomiya, I.; Naito, T. Tetrahedron Lett. 1995, 36, 253. (c) Naito, T.; Tajiri, K.; Harimoto, T.; Ninomiya, I.; Kiguchi, T. Tetrahedron Lett. 1994, 35, 2205. (d) Booth, S. E.; Jenkins, P. R.; Swain, C. J.; Sweeney, J. B.; J. Chem. Soc., Perkin Trans. 1 1994, 3499. (e) Parker, K.; Fokas, D. J. Org. Chem. 1994, 59, 3927. (f) Grissom, J. W.; Klingberg, D. J. Org. Chem. 1993, 58, 6559. (g) Pattenden, G.; Schulz, D. J. Tetrahedron Lett. 1993, 34, 6787. (h) Hatem, J.; Henriet-Bernard, C.; Grimaldi, J.; Maurin, R. Tetrahedron Lett. 1992, 33, 1057. (i) Marco-Contelles, J.; Pozuelo, C.; Jimeno, M. L.; Martinez, L.; Martinez-Grau, A. J. Org. Chem. 1992, 57, 2625. (j) Marco-Contelles, J.; Ruiz, P.; Sanchez, B.; Jimeno, M. L. Tetrahedron Lett. 1992, 33, 5261. (k) Parker, K. A.; Fokas, D. J. Am. Chem. Soc. 1992, 114, 9688. (l) Marco-Contelles, J.; Martinez, L.; Martinez-Grau, A.; Pozuelo, C.; Jimeno, M. L. Tetrahedron Lett. 1991, 32, 6437. (m) Booth, S. E.; Jenkins, P. R.; Swain, C. J. J. Chem. Soc., Chem. Commun. 1991, 1248. (n) Marco-Contelles, J.; Martinez, L.; Martinez- Grau, A. Tetrahedron: Asymmetry 1991, 2, 961. (o) Enholm, E. J.; Burnoff, J. A.; Jaramillo, L. M. Tetrahedron Lett. 1990, 31, 3727. (p) Parker, K. A.; Spero, D. M.; Van Epp, J. J. Org. Chem. 1988, 53, 4628. (q) Bartlett, P. A.; McLaren, K. L.; Ting, P. C. J. Am. Chem. Soc. 1988, 110, 1633. (r) Hart, D. J.; Seely, F. J. Am. Chem. Soc. 1988, 110, 1631. (s) Corey, E. J.; Pyne, S. G. Tetrahedron Lett. 1983, 24, 2821.
25. For previous work on both inter- and intramolecular free radical additions to oxime ethers, see: (a) Chiara, J. L.; Marco-Contelles, J.; Khair, N.; Gallego, P.; Destabel, C.; Bernabe, M. J. Org. Chem. 1995, 60, 6010. (b) Kiguchi, T.; Tajiri, K.; Ninomiya, I.; Naito, T. Tetrahedron Lett. 1995, 36, 253. (c) Naito, T.; Tajiri, K.; Harimoto, T.; Ninomiya, I.; Kiguchi, T. Tetrahedron Lett. 1994, 35, 2205. (d) Booth, S. E.; Jenkins, P. R.; Swain, C. J.; Sweeney, J. B.; J. Chem. Soc., Perkin Trans. 1 1994, 3499. (e) Parker, K.; Fokas, D. J. Org. Chem. 1994, 59, 3927. (f) Grissom, J. W.; Klingberg, D. J. Org. Chem. 1993, 58, 6559. (g) Pattenden, G.; Schulz, D. J. Tetrahedron Lett. 1993, 34, 6787. (h) Hatem, J.; Henriet-Bernard, C.; Grimaldi, J.; Maurin, R. Tetrahedron Lett. 1992, 33, 1057. (i) Marco-Contelles, J.; Pozuelo, C.; Jimeno, M. L.; Martinez, L.; Martinez-Grau, A. J. Org. Chem. 1992, 57, 2625. (j) Marco-Contelles, J.; Ruiz, P.; Sanchez, B.; Jimeno, M. L. Tetrahedron Lett. 1992, 33, 5261. (k) Parker, K. A.; Fokas, D. J. Am. Chem. Soc. 1992, 114, 9688. (l) Marco-Contelles, J.; Martinez, L.; Martinez-Grau, A.; Pozuelo, C.; Jimeno, M. L. Tetrahedron Lett. 1991, 32, 6437. (m) Booth, S. E.; Jenkins, P. R.; Swain, C. J. J. Chem. Soc., Chem. Commun. 1991, 1248. (n) Marco-Contelles, J.; Martinez, L.; Martinez- Grau, A. Tetrahedron: Asymmetry 1991, 2, 961. (o) Enholm, E. J.; Burnoff, J. A.; Jaramillo, L. M. Tetrahedron Lett. 1990, 31, 3727. (p) Parker, K. A.; Spero, D. M.; Van Epp, J. J. Org. Chem. 1988, 53, 4628. (q) Bartlett, P. A.; McLaren, K. L.; Ting, P. C. J. Am. Chem. Soc. 1988, 110, 1633. (r) Hart, D. J.; Seely, F. J. Am. Chem. Soc. 1988, 110, 1631. (s) Corey, E. J.; Pyne, S. G. Tetrahedron Lett. 1983, 24, 2821.
26. For previous work on both inter- and intramolecular free radical additions to oxime ethers, see: (a) Chiara, J. L.; Marco-Contelles, J.; Khair, N.; Gallego, P.; Destabel, C.; Bernabe, M. J. Org. Chem. 1995, 60, 6010. (b) Kiguchi, T.; Tajiri, K.; Ninomiya, I.; Naito, T. Tetrahedron Lett. 1995, 36, 253. (c) Naito, T.; Tajiri, K.; Harimoto, T.; Ninomiya, I.; Kiguchi, T. Tetrahedron Lett. 1994, 35, 2205. (d) Booth, S. E.; Jenkins, P. R.; Swain, C. J.; Sweeney, J. B.; J. Chem. Soc., Perkin Trans. 1 1994, 3499. (e) Parker, K.; Fokas, D. J. Org. Chem. 1994, 59, 3927. (f) Grissom, J. W.; Klingberg, D. J. Org. Chem. 1993, 58, 6559. (g) Pattenden, G.; Schulz, D. J. Tetrahedron Lett. 1993, 34, 6787. (h) Hatem, J.; Henriet-Bernard, C.; Grimaldi, J.; Maurin, R. Tetrahedron Lett. 1992, 33, 1057. (i) Marco-Contelles, J.; Pozuelo, C.; Jimeno, M. L.; Martinez, L.; Martinez-Grau, A. J. Org. Chem. 1992, 57, 2625. (j) Marco-Contelles, J.; Ruiz, P.; Sanchez, B.; Jimeno, M. L. Tetrahedron Lett. 1992, 33, 5261. (k) Parker, K. A.; Fokas, D. J. Am. Chem. Soc. 1992, 114, 9688. (l) Marco-Contelles, J.; Martinez, L.; Martinez-Grau, A.; Pozuelo, C.; Jimeno, M. L. Tetrahedron Lett. 1991, 32, 6437. (m) Booth, S. E.; Jenkins, P. R.; Swain, C. J. J. Chem. Soc., Chem. Commun. 1991, 1248. (n) Marco-Contelles, J.; Martinez, L.; Martinez- Grau, A. Tetrahedron: Asymmetry 1991, 2, 961. (o) Enholm, E. J.; Burnoff, J. A.; Jaramillo, L. M. Tetrahedron Lett. 1990, 31, 3727. (p) Parker, K. A.; Spero, D. M.; Van Epp, J. J. Org. Chem. 1988, 53, 4628. (q) Bartlett, P. A.; McLaren, K. L.; Ting, P. C. J. Am. Chem. Soc. 1988, 110, 1633. (r) Hart, D. J.; Seely, F. J. Am. Chem. Soc. 1988, 110, 1631. (s) Corey, E. J.; Pyne, S. G. Tetrahedron Lett. 1983, 24, 2821.
27. For previous work on both inter- and intramolecular free radical additions to oxime ethers, see: (a) Chiara, J. L.; Marco-Contelles, J.; Khair, N.; Gallego, P.; Destabel, C.; Bernabe, M. J. Org. Chem. 1995, 60, 6010. (b) Kiguchi, T.; Tajiri, K.; Ninomiya, I.; Naito, T. Tetrahedron Lett. 1995, 36, 253. (c) Naito, T.; Tajiri, K.; Harimoto, T.; Ninomiya, I.; Kiguchi, T. Tetrahedron Lett. 1994, 35, 2205. (d) Booth, S. E.; Jenkins, P. R.; Swain, C. J.; Sweeney, J. B.; J. Chem. Soc., Perkin Trans. 1 1994, 3499. (e) Parker, K.; Fokas, D. J. Org. Chem. 1994, 59, 3927. (f) Grissom, J. W.; Klingberg, D. J. Org. Chem. 1993, 58, 6559. (g) Pattenden, G.; Schulz, D. J. Tetrahedron Lett. 1993, 34, 6787. (h) Hatem, J.; Henriet-Bernard, C.; Grimaldi, J.; Maurin, R. Tetrahedron Lett. 1992, 33, 1057. (i) Marco-Contelles, J.; Pozuelo, C.; Jimeno, M. L.; Martinez, L.; Martinez-Grau, A. J. Org. Chem. 1992, 57, 2625. (j) Marco-Contelles, J.; Ruiz, P.; Sanchez, B.; Jimeno, M. L. Tetrahedron Lett. 1992, 33, 5261. (k) Parker, K. A.; Fokas, D. J. Am. Chem. Soc. 1992, 114, 9688. (l) Marco-Contelles, J.; Martinez, L.; Martinez-Grau, A.; Pozuelo, C.; Jimeno, M. L. Tetrahedron Lett. 1991, 32, 6437. (m) Booth, S. E.; Jenkins, P. R.; Swain, C. J. J. Chem. Soc., Chem. Commun. 1991, 1248. (n) Marco-Contelles, J.; Martinez, L.; Martinez- Grau, A. Tetrahedron: Asymmetry 1991, 2, 961. (o) Enholm, E. J.; Burnoff, J. A.; Jaramillo, L. M. Tetrahedron Lett. 1990, 31, 3727. (p) Parker, K. A.; Spero, D. M.; Van Epp, J. J. Org. Chem. 1988, 53, 4628. (q) Bartlett, P. A.; McLaren, K. L.; Ting, P. C. J. Am. Chem. Soc. 1988, 110, 1633. (r) Hart, D. J.; Seely, F. J. Am. Chem. Soc. 1988, 110, 1631. (s) Corey, E. J.; Pyne, S. G. Tetrahedron Lett. 1983, 24, 2821.
28. For previous work on both inter- and intramolecular free radical additions to oxime ethers, see: (a) Chiara, J. L.; Marco-Contelles, J.; Khair, N.; Gallego, P.; Destabel, C.; Bernabe, M. J. Org. Chem. 1995, 60, 6010. (b) Kiguchi, T.; Tajiri, K.; Ninomiya, I.; Naito, T. Tetrahedron Lett. 1995, 36, 253. (c) Naito, T.; Tajiri, K.; Harimoto, T.; Ninomiya, I.; Kiguchi, T. Tetrahedron Lett. 1994, 35, 2205. (d) Booth, S. E.; Jenkins, P. R.; Swain, C. J.; Sweeney, J. B.; J. Chem. Soc., Perkin Trans. 1 1994, 3499. (e) Parker, K.; Fokas, D. J. Org. Chem. 1994, 59, 3927. (f) Grissom, J. W.; Klingberg, D. J. Org. Chem. 1993, 58, 6559. (g) Pattenden, G.; Schulz, D. J. Tetrahedron Lett. 1993, 34, 6787. (h) Hatem, J.; Henriet-Bernard, C.; Grimaldi, J.; Maurin, R. Tetrahedron Lett. 1992, 33, 1057. (i) Marco-Contelles, J.; Pozuelo, C.; Jimeno, M. L.; Martinez, L.; Martinez-Grau, A. J. Org. Chem. 1992, 57, 2625. (j) Marco-Contelles, J.; Ruiz, P.; Sanchez, B.; Jimeno, M. L. Tetrahedron Lett. 1992, 33, 5261. (k) Parker, K. A.; Fokas, D. J. Am. Chem. Soc. 1992, 114, 9688. (l) Marco-Contelles, J.; Martinez, L.; Martinez-Grau, A.; Pozuelo, C.; Jimeno, M. L. Tetrahedron Lett. 1991, 32, 6437. (m) Booth, S. E.; Jenkins, P. R.; Swain, C. J. J. Chem. Soc., Chem. Commun. 1991, 1248. (n) Marco-Contelles, J.; Martinez, L.; Martinez- Grau, A. Tetrahedron: Asymmetry 1991, 2, 961. (o) Enholm, E. J.; Burnoff, J. A.; Jaramillo, L. M. Tetrahedron Lett. 1990, 31, 3727. (p) Parker, K. A.; Spero, D. M.; Van Epp, J. J. Org. Chem. 1988, 53, 4628. (q) Bartlett, P. A.; McLaren, K. L.; Ting, P. C. J. Am. Chem. Soc. 1988, 110, 1633. (r) Hart, D. J.; Seely, F. J. Am. Chem. Soc. 1988, 110, 1631. (s) Corey, E. J.; Pyne, S. G. Tetrahedron Lett. 1983, 24, 2821.
29. For previous work on both inter- and intramolecular free radical additions to oxime ethers, see: (a) Chiara, J. L.; Marco-Contelles, J.; Khair, N.; Gallego, P.; Destabel, C.; Bernabe, M. J. Org. Chem. 1995, 60, 6010. (b) Kiguchi, T.; Tajiri, K.; Ninomiya, I.; Naito, T. Tetrahedron Lett. 1995, 36, 253. (c) Naito, T.; Tajiri, K.; Harimoto, T.; Ninomiya, I.; Kiguchi, T. Tetrahedron Lett. 1994, 35, 2205. (d) Booth, S. E.; Jenkins, P. R.; Swain, C. J.; Sweeney, J. B.; J. Chem. Soc., Perkin Trans. 1 1994, 3499. (e) Parker, K.; Fokas, D. J. Org. Chem. 1994, 59, 3927. (f) Grissom, J. W.; Klingberg, D. J. Org. Chem. 1993, 58, 6559. (g) Pattenden, G.; Schulz, D. J. Tetrahedron Lett. 1993, 34, 6787. (h) Hatem, J.; Henriet-Bernard, C.; Grimaldi, J.; Maurin, R. Tetrahedron Lett. 1992, 33, 1057. (i) Marco-Contelles, J.; Pozuelo, C.; Jimeno, M. L.; Martinez, L.; Martinez-Grau, A. J. Org. Chem. 1992, 57, 2625. (j) Marco-Contelles, J.; Ruiz, P.; Sanchez, B.; Jimeno, M. L. Tetrahedron Lett. 1992, 33, 5261. (k) Parker, K. A.; Fokas, D. J. Am. Chem. Soc. 1992, 114, 9688. (l) Marco-Contelles, J.; Martinez, L.; Martinez-Grau, A.; Pozuelo, C.; Jimeno, M. L. Tetrahedron Lett. 1991, 32, 6437. (m) Booth, S. E.; Jenkins, P. R.; Swain, C. J. J. Chem. Soc., Chem. Commun. 1991, 1248. (n) Marco-Contelles, J.; Martinez, L.; Martinez- Grau, A. Tetrahedron: Asymmetry 1991, 2, 961. (o) Enholm, E. J.; Burnoff, J. A.; Jaramillo, L. M. Tetrahedron Lett. 1990, 31, 3727. (p) Parker, K. A.; Spero, D. M.; Van Epp, J. J. Org. Chem. 1988, 53, 4628. (q) Bartlett, P. A.; McLaren, K. L.; Ting, P. C. J. Am. Chem. Soc. 1988, 110, 1633. (r) Hart, D. J.; Seely, F. J. Am. Chem. Soc. 1988, 110, 1631. (s) Corey, E. J.; Pyne, S. G. Tetrahedron Lett. 1983, 24, 2821.
30. For previous work on both inter- and intramolecular free radical additions to oxime ethers, see: (a) Chiara, J. L.; Marco-Contelles, J.; Khair, N.; Gallego, P.; Destabel, C.; Bernabe, M. J. Org. Chem. 1995, 60, 6010. (b) Kiguchi, T.; Tajiri, K.; Ninomiya, I.; Naito, T. Tetrahedron Lett. 1995, 36, 253. (c) Naito, T.; Tajiri, K.; Harimoto, T.; Ninomiya, I.; Kiguchi, T. Tetrahedron Lett. 1994, 35, 2205. (d) Booth, S. E.; Jenkins, P. R.; Swain, C. J.; Sweeney, J. B.; J. Chem. Soc., Perkin Trans. 1 1994, 3499. (e) Parker, K.; Fokas, D. J. Org. Chem. 1994, 59, 3927. (f) Grissom, J. W.; Klingberg, D. J. Org. Chem. 1993, 58, 6559. (g) Pattenden, G.; Schulz, D. J. Tetrahedron Lett. 1993, 34, 6787. (h) Hatem, J.; Henriet-Bernard, C.; Grimaldi, J.; Maurin, R. Tetrahedron Lett. 1992, 33, 1057. (i) Marco-Contelles, J.; Pozuelo, C.; Jimeno, M. L.; Martinez, L.; Martinez-Grau, A. J. Org. Chem. 1992, 57, 2625. (j) Marco-Contelles, J.; Ruiz, P.; Sanchez, B.; Jimeno, M. L. Tetrahedron Lett. 1992, 33, 5261. (k) Parker, K. A.; Fokas, D. J. Am. Chem. Soc. 1992, 114, 9688. (l) Marco-Contelles, J.; Martinez, L.; Martinez-Grau, A.; Pozuelo, C.; Jimeno, M. L. Tetrahedron Lett. 1991, 32, 6437. (m) Booth, S. E.; Jenkins, P. R.; Swain, C. J. J. Chem. Soc., Chem. Commun. 1991, 1248. (n) Marco-Contelles, J.; Martinez, L.; Martinez- Grau, A. Tetrahedron: Asymmetry 1991, 2, 961. (o) Enholm, E. J.; Burnoff, J. A.; Jaramillo, L. M. Tetrahedron Lett. 1990, 31, 3727. (p) Parker, K. A.; Spero, D. M.; Van Epp, J. J. Org. Chem. 1988, 53, 4628. (q) Bartlett, P. A.; McLaren, K. L.; Ting, P. C. J. Am. Chem. Soc. 1988, 110, 1633. (r) Hart, D. J.; Seely, F. J. Am. Chem. Soc. 1988, 110, 1631. (s) Corey, E. J.; Pyne, S. G. Tetrahedron Lett. 1983, 24, 2821.
31. For previous work on both inter- and intramolecular free radical additions to oxime ethers, see: (a) Chiara, J. L.; Marco-Contelles, J.; Khair, N.; Gallego, P.; Destabel, C.; Bernabe, M. J. Org. Chem. 1995, 60, 6010. (b) Kiguchi, T.; Tajiri, K.; Ninomiya, I.; Naito, T. Tetrahedron Lett. 1995, 36, 253. (c) Naito, T.; Tajiri, K.; Harimoto, T.; Ninomiya, I.; Kiguchi, T. Tetrahedron Lett. 1994, 35, 2205. (d) Booth, S. E.; Jenkins, P. R.; Swain, C. J.; Sweeney, J. B.; J. Chem. Soc., Perkin Trans. 1 1994, 3499. (e) Parker, K.; Fokas, D. J. Org. Chem. 1994, 59, 3927. (f) Grissom, J. W.; Klingberg, D. J. Org. Chem. 1993, 58, 6559. (g) Pattenden, G.; Schulz, D. J. Tetrahedron Lett. 1993, 34, 6787. (h) Hatem, J.; Henriet-Bernard, C.; Grimaldi, J.; Maurin, R. Tetrahedron Lett. 1992, 33, 1057. (i) Marco-Contelles, J.; Pozuelo, C.; Jimeno, M. L.; Martinez, L.; Martinez-Grau, A. J. Org. Chem. 1992, 57, 2625. (j) Marco-Contelles, J.; Ruiz, P.; Sanchez, B.; Jimeno, M. L. Tetrahedron Lett. 1992, 33, 5261. (k) Parker, K. A.; Fokas, D. J. Am. Chem. Soc. 1992, 114, 9688. (l) Marco-Contelles, J.; Martinez, L.; Martinez-Grau, A.; Pozuelo, C.; Jimeno, M. L. Tetrahedron Lett. 1991, 32, 6437. (m) Booth, S. E.; Jenkins, P. R.; Swain, C. J. J. Chem. Soc., Chem. Commun. 1991, 1248. (n) Marco-Contelles, J.; Martinez, L.; Martinez- Grau, A. Tetrahedron: Asymmetry 1991, 2, 961. (o) Enholm, E. J.; Burnoff, J. A.; Jaramillo, L. M. Tetrahedron Lett. 1990, 31, 3727. (p) Parker, K. A.; Spero, D. M.; Van Epp, J. J. Org. Chem. 1988, 53, 4628. (q) Bartlett, P. A.; McLaren, K. L.; Ting, P. C. J. Am. Chem. Soc. 1988, 110, 1633. (r) Hart, D. J.; Seely, F. J. Am. Chem. Soc. 1988, 110, 1631. (s) Corey, E. J.; Pyne, S. G. Tetrahedron Lett. 1983, 24, 2821.
32. For previous work on both inter- and intramolecular free radical additions to oxime ethers, see: (a) Chiara, J. L.; Marco-Contelles, J.; Khair, N.; Gallego, P.; Destabel, C.; Bernabe, M. J. Org. Chem. 1995, 60, 6010. (b) Kiguchi, T.; Tajiri, K.; Ninomiya, I.; Naito, T. Tetrahedron Lett. 1995, 36, 253. (c) Naito, T.; Tajiri, K.; Harimoto, T.; Ninomiya, I.; Kiguchi, T. Tetrahedron Lett. 1994, 35, 2205. (d) Booth, S. E.; Jenkins, P. R.; Swain, C. J.; Sweeney, J. B.; J. Chem. Soc., Perkin Trans. 1 1994, 3499. (e) Parker, K.; Fokas, D. J. Org. Chem. 1994, 59, 3927. (f) Grissom, J. W.; Klingberg, D. J. Org. Chem. 1993, 58, 6559. (g) Pattenden, G.; Schulz, D. J. Tetrahedron Lett. 1993, 34, 6787. (h) Hatem, J.; Henriet-Bernard, C.; Grimaldi, J.; Maurin, R. Tetrahedron Lett. 1992, 33, 1057. (i) Marco-Contelles, J.; Pozuelo, C.; Jimeno, M. L.; Martinez, L.; Martinez-Grau, A. J. Org. Chem. 1992, 57, 2625. (j) Marco-Contelles, J.; Ruiz, P.; Sanchez, B.; Jimeno, M. L. Tetrahedron Lett. 1992, 33, 5261. (k) Parker, K. A.; Fokas, D. J. Am. Chem. Soc. 1992, 114, 9688. (l) Marco-Contelles, J.; Martinez, L.; Martinez-Grau, A.; Pozuelo, C.; Jimeno, M. L. Tetrahedron Lett. 1991, 32, 6437. (m) Booth, S. E.; Jenkins, P. R.; Swain, C. J. J. Chem. Soc., Chem. Commun. 1991, 1248. (n) Marco-Contelles, J.; Martinez, L.; Martinez- Grau, A. Tetrahedron: Asymmetry 1991, 2, 961. (o) Enholm, E. J.; Burnoff, J. A.; Jaramillo, L. M. Tetrahedron Lett. 1990, 31, 3727. (p) Parker, K. A.; Spero, D. M.; Van Epp, J. J. Org. Chem. 1988, 53, 4628. (q) Bartlett, P. A.; McLaren, K. L.; Ting, P. C. J. Am. Chem. Soc. 1988, 110, 1633. (r) Hart, D. J.; Seely, F. J. Am. Chem. Soc. 1988, 110, 1631. (s) Corey, E. J.; Pyne, S. G. Tetrahedron Lett. 1983, 24, 2821.
33. For previous work on both inter- and intramolecular free radical additions to oxime ethers, see: (a) Chiara, J. L.; Marco-Contelles, J.; Khair, N.; Gallego, P.; Destabel, C.; Bernabe, M. J. Org. Chem. 1995, 60, 6010. (b) Kiguchi, T.; Tajiri, K.; Ninomiya, I.; Naito, T. Tetrahedron Lett. 1995, 36, 253. (c) Naito, T.; Tajiri, K.; Harimoto, T.; Ninomiya, I.; Kiguchi, T. Tetrahedron Lett. 1994, 35, 2205. (d) Booth, S. E.; Jenkins, P. R.; Swain, C. J.; Sweeney, J. B.; J. Chem. Soc., Perkin Trans. 1 1994, 3499. (e) Parker, K.; Fokas, D. J. Org. Chem. 1994, 59, 3927. (f) Grissom, J. W.; Klingberg, D. J. Org. Chem. 1993, 58, 6559. (g) Pattenden, G.; Schulz, D. J. Tetrahedron Lett. 1993, 34, 6787. (h) Hatem, J.; Henriet-Bernard, C.; Grimaldi, J.; Maurin, R. Tetrahedron Lett. 1992, 33, 1057. (i) Marco-Contelles, J.; Pozuelo, C.; Jimeno, M. L.; Martinez, L.; Martinez-Grau, A. J. Org. Chem. 1992, 57, 2625. (j) Marco-Contelles, J.; Ruiz, P.; Sanchez, B.; Jimeno, M. L. Tetrahedron Lett. 1992, 33, 5261. (k) Parker, K. A.; Fokas, D. J. Am. Chem. Soc. 1992, 114, 9688. (l) Marco-Contelles, J.; Martinez, L.; Martinez-Grau, A.; Pozuelo, C.; Jimeno, M. L. Tetrahedron Lett. 1991, 32, 6437. (m) Booth, S. E.; Jenkins, P. R.; Swain, C. J. J. Chem. Soc., Chem. Commun. 1991, 1248. (n) Marco-Contelles, J.; Martinez, L.; Martinez- Grau, A. Tetrahedron: Asymmetry 1991, 2, 961. (o) Enholm, E. J.; Burnoff, J. A.; Jaramillo, L. M. Tetrahedron Lett. 1990, 31, 3727. (p) Parker, K. A.; Spero, D. M.; Van Epp, J. J. Org. Chem. 1988, 53, 4628. (q) Bartlett, P. A.; McLaren, K. L.; Ting, P. C. J. Am. Chem. Soc. 1988, 110, 1633. (r) Hart, D. J.; Seely, F. J. Am. Chem. Soc. 1988, 110, 1631. (s) Corey, E. J.; Pyne, S. G. Tetrahedron Lett. 1983, 24, 2821.
34. For previous work on both inter- and intramolecular free radical additions to oxime ethers, see: (a) Chiara, J. L.; Marco-Contelles, J.; Khair, N.; Gallego, P.; Destabel, C.; Bernabe, M. J. Org. Chem. 1995, 60, 6010. (b) Kiguchi, T.; Tajiri, K.; Ninomiya, I.; Naito, T. Tetrahedron Lett. 1995, 36, 253. (c) Naito, T.; Tajiri, K.; Harimoto, T.; Ninomiya, I.; Kiguchi, T. Tetrahedron Lett. 1994, 35, 2205. (d) Booth, S. E.; Jenkins, P. R.; Swain, C. J.; Sweeney, J. B.; J. Chem. Soc., Perkin Trans. 1 1994, 3499. (e) Parker, K.; Fokas, D. J. Org. Chem. 1994, 59, 3927. (f) Grissom, J. W.; Klingberg, D. J. Org. Chem. 1993, 58, 6559. (g) Pattenden, G.; Schulz, D. J. Tetrahedron Lett. 1993, 34, 6787. (h) Hatem, J.; Henriet-Bernard, C.; Grimaldi, J.; Maurin, R. Tetrahedron Lett. 1992, 33, 1057. (i) Marco-Contelles, J.; Pozuelo, C.; Jimeno, M. L.; Martinez, L.; Martinez-Grau, A. J. Org. Chem. 1992, 57, 2625. (j) Marco-Contelles, J.; Ruiz, P.; Sanchez, B.; Jimeno, M. L. Tetrahedron Lett. 1992, 33, 5261. (k) Parker, K. A.; Fokas, D. J. Am. Chem. Soc. 1992, 114, 9688. (l) Marco-Contelles, J.; Martinez, L.; Martinez-Grau, A.; Pozuelo, C.; Jimeno, M. L. Tetrahedron Lett. 1991, 32, 6437. (m) Booth, S. E.; Jenkins, P. R.; Swain, C. J. J. Chem. Soc., Chem. Commun. 1991, 1248. (n) Marco-Contelles, J.; Martinez, L.; Martinez- Grau, A. Tetrahedron: Asymmetry 1991, 2, 961. (o) Enholm, E. J.; Burnoff, J. A.; Jaramillo, L. M. Tetrahedron Lett. 1990, 31, 3727. (p) Parker, K. A.; Spero, D. M.; Van Epp, J. J. Org. Chem. 1988, 53, 4628. (q) Bartlett, P. A.; McLaren, K. L.; Ting, P. C. J. Am. Chem. Soc. 1988, 110, 1633. (r) Hart, D. J.; Seely, F. J. Am. Chem. Soc. 1988, 110, 1631. (s) Corey, E. J.; Pyne, S. G. Tetrahedron Lett. 1983, 24, 2821.
35. For previous work on both inter- and intramolecular free radical additions to oxime ethers, see: (a) Chiara, J. L.; Marco-Contelles, J.; Khair, N.; Gallego, P.; Destabel, C.; Bernabe, M. J. Org. Chem. 1995, 60, 6010. (b) Kiguchi, T.; Tajiri, K.; Ninomiya, I.; Naito, T. Tetrahedron Lett. 1995, 36, 253. (c) Naito, T.; Tajiri, K.; Harimoto, T.; Ninomiya, I.; Kiguchi, T. Tetrahedron Lett. 1994, 35, 2205. (d) Booth, S. E.; Jenkins, P. R.; Swain, C. J.; Sweeney, J. B.; J. Chem. Soc., Perkin Trans. 1 1994, 3499. (e) Parker, K.; Fokas, D. J. Org. Chem. 1994, 59, 3927. (f) Grissom, J. W.; Klingberg, D. J. Org. Chem. 1993, 58, 6559. (g) Pattenden, G.; Schulz, D. J. Tetrahedron Lett. 1993, 34, 6787. (h) Hatem, J.; Henriet-Bernard, C.; Grimaldi, J.; Maurin, R. Tetrahedron Lett. 1992, 33, 1057. (i) Marco-Contelles, J.; Pozuelo, C.; Jimeno, M. L.; Martinez, L.; Martinez-Grau, A. J. Org. Chem. 1992, 57, 2625. (j) Marco-Contelles, J.; Ruiz, P.; Sanchez, B.; Jimeno, M. L. Tetrahedron Lett. 1992, 33, 5261. (k) Parker, K. A.; Fokas, D. J. Am. Chem. Soc. 1992, 114, 9688. (l) Marco-Contelles, J.; Martinez, L.; Martinez-Grau, A.; Pozuelo, C.; Jimeno, M. L. Tetrahedron Lett. 1991, 32, 6437. (m) Booth, S. E.; Jenkins, P. R.; Swain, C. J. J. Chem. Soc., Chem. Commun. 1991, 1248. (n) Marco-Contelles, J.; Martinez, L.; Martinez- Grau, A. Tetrahedron: Asymmetry 1991, 2, 961. (o) Enholm, E. J.; Burnoff, J. A.; Jaramillo, L. M. Tetrahedron Lett. 1990, 31, 3727. (p) Parker, K. A.; Spero, D. M.; Van Epp, J. J. Org. Chem. 1988, 53, 4628. (q) Bartlett, P. A.; McLaren, K. L.; Ting, P. C. J. Am. Chem. Soc. 1988, 110, 1633. (r) Hart, D. J.; Seely, F. J. Am. Chem. Soc. 1988, 110, 1631. (s) Corey, E. J.; Pyne, S. G. Tetrahedron Lett. 1983, 24, 2821.
36. For previous work on both inter- and intramolecular free radical additions to oxime ethers, see: (a) Chiara, J. L.; Marco-Contelles, J.; Khair, N.; Gallego, P.; Destabel, C.; Bernabe, M. J. Org. Chem. 1995, 60, 6010. (b) Kiguchi, T.; Tajiri, K.; Ninomiya, I.; Naito, T. Tetrahedron Lett. 1995, 36, 253. (c) Naito, T.; Tajiri, K.; Harimoto, T.; Ninomiya, I.; Kiguchi, T. Tetrahedron Lett. 1994, 35, 2205. (d) Booth, S. E.; Jenkins, P. R.; Swain, C. J.; Sweeney, J. B.; J. Chem. Soc., Perkin Trans. 1 1994, 3499. (e) Parker, K.; Fokas, D. J. Org. Chem. 1994, 59, 3927. (f) Grissom, J. W.; Klingberg, D. J. Org. Chem. 1993, 58, 6559. (g) Pattenden, G.; Schulz, D. J. Tetrahedron Lett. 1993, 34, 6787. (h) Hatem, J.; Henriet-Bernard, C.; Grimaldi, J.; Maurin, R. Tetrahedron Lett. 1992, 33, 1057. (i) Marco-Contelles, J.; Pozuelo, C.; Jimeno, M. L.; Martinez, L.; Martinez-Grau, A. J. Org. Chem. 1992, 57, 2625. (j) Marco-Contelles, J.; Ruiz, P.; Sanchez, B.; Jimeno, M. L. Tetrahedron Lett. 1992, 33, 5261. (k) Parker, K. A.; Fokas, D. J. Am. Chem. Soc. 1992, 114, 9688. (l) Marco-Contelles, J.; Martinez, L.; Martinez-Grau, A.; Pozuelo, C.; Jimeno, M. L. Tetrahedron Lett. 1991, 32, 6437. (m) Booth, S. E.; Jenkins, P. R.; Swain, C. J. J. Chem. Soc., Chem. Commun. 1991, 1248. (n) Marco-Contelles, J.; Martinez, L.; Martinez-Grau, A. Tetrahedron: Asymmetry 1991, 2, 961. (o) Enholm, E. J.; Burnoff, J. A.; Jaramillo, L. M. Tetrahedron Lett. 1990, 31, 3727. (p) Parker, K. A.; Spero, D. M.; Van Epp, J. J. Org. Chem. 1988, 53, 4628. (q) Bartlett, P. A.; McLaren, K. L.; Ting, P. C. J. Am. Chem. Soc. 1988, 110, 1633. (r) Hart, D. J.; Seely, F. J. Am. Chem. Soc. 1988, 110, 1631. (s) Corey, E. J.; Pyne, S. G. Tetrahedron Lett. 1983, 24, 2821.
37. For previous work on both inter- and intramolecular free radical additions to oxime ethers, see: (a) Chiara, J. L.; Marco-Contelles, J.; Khair, N.; Gallego, P.; Destabel, C.; Bernabe, M. J. Org. Chem. 1995, 60, 6010. (b) Kiguchi, T.; Tajiri, K.; Ninomiya, I.; Naito, T. Tetrahedron Lett. 1995, 36, 253. (c) Naito, T.; Tajiri, K.; Harimoto, T.; Ninomiya, I.; Kiguchi, T. Tetrahedron Lett. 1994, 35, 2205. (d) Booth, S. E.; Jenkins, P. R.; Swain, C. J.; Sweeney, J. B.; J. Chem. Soc., Perkin Trans. 1 1994, 3499. (e) Parker, K.; Fokas, D. J. Org. Chem. 1994, 59, 3927. (f) Grissom, J. W.; Klingberg, D. J. Org. Chem. 1993, 58, 6559. (g) Pattenden, G.; Schulz, D. J. Tetrahedron Lett. 1993, 34, 6787. (h) Hatem, J.; Henriet-Bernard, C.; Grimaldi, J.; Maurin, R. Tetrahedron Lett. 1992, 33, 1057. (i) Marco-Contelles, J.; Pozuelo, C.; Jimeno, M. L.; Martinez, L.; Martinez-Grau, A. J. Org. Chem. 1992, 57, 2625. (j) Marco-Contelles, J.; Ruiz, P.; Sanchez, B.; Jimeno, M. L. Tetrahedron Lett. 1992, 33, 5261. (k) Parker, K. A.; Fokas, D. J. Am. Chem. Soc. 1992, 114, 9688. (l) Marco-Contelles, J.; Martinez, L.; Martinez-Grau, A.; Pozuelo, C.; Jimeno, M. L. Tetrahedron Lett. 1991, 32, 6437. (m) Booth, S. E.; Jenkins, P. R.; Swain, C. J. J. Chem. Soc., Chem. Commun. 1991, 1248. (n) Marco-Contelles, J.; Martinez, L.; Martinez- Grau, A. Tetrahedron: Asymmetry 1991, 2, 961. (o) Enholm, E. J.; Burnoff, J. A.; Jaramillo, L. M. Tetrahedron Lett. 1990, 31, 3727. (p) Parker, K. A.; Spero, D. M.; Van Epp, J. J. Org. Chem. 1988, 53, 4628. (q) Bartlett, P. A.; McLaren, K. L.; Ting, P. C. J. Am. Chem. Soc. 1988, 110, 1633. (r) Hart, D. J.; Seely, F. J. Am. Chem. Soc. 1988, 110, 1631. (s) Corey, E. J.; Pyne, S. G. Tetrahedron Lett. 1983, 24, 2821.
38. For previous work on both inter- and intramolecular free radical additions to oxime ethers, see: (a) Chiara, J. L.; Marco-Contelles, J.; Khair, N.; Gallego, P.; Destabel, C.; Bernabe, M. J. Org. Chem. 1995, 60, 6010. (b) Kiguchi, T.; Tajiri, K.; Ninomiya, I.; Naito, T. Tetrahedron Lett. 1995, 36, 253. (c) Naito, T.; Tajiri, K.; Harimoto, T.; Ninomiya, I.; Kiguchi, T. Tetrahedron Lett. 1994, 35, 2205. (d) Booth, S. E.; Jenkins, P. R.; Swain, C. J.; Sweeney, J. B.; J. Chem. Soc., Perkin Trans. 1 1994, 3499. (e) Parker, K.; Fokas, D. J. Org. Chem. 1994, 59, 3927. (f) Grissom, J. W.; Klingberg, D. J. Org. Chem. 1993, 58, 6559. (g) Pattenden, G.; Schulz, D. J. Tetrahedron Lett. 1993, 34, 6787. (h) Hatem, J.; Henriet-Bernard, C.; Grimaldi, J.; Maurin, R. Tetrahedron Lett. 1992, 33, 1057. (i) Marco-Contelles, J.; Pozuelo, C.; Jimeno, M. L.; Martinez, L.; Martinez-Grau, A. J. Org. Chem. 1992, 57, 2625. (j) Marco-Contelles, J.; Ruiz, P.; Sanchez, B.; Jimeno, M. L. Tetrahedron Lett. 1992, 33, 5261. (k) Parker, K. A.; Fokas, D. J. Am. Chem. Soc. 1992, 114, 9688. (l) Marco-Contelles, J.; Martinez, L.; Martinez-Grau, A.; Pozuelo, C.; Jimeno, M. L. Tetrahedron Lett. 1991, 32, 6437. (m) Booth, S. E.; Jenkins, P. R.; Swain, C. J. J. Chem. Soc., Chem. Commun. 1991, 1248. (n) Marco-Contelles, J.; Martinez, L.; Martinez- Grau, A. Tetrahedron: Asymmetry 1991, 2, 961. (o) Enholm, E. J.; Burnoff, J. A.; Jaramillo, L. M. Tetrahedron Lett. 1990, 31, 3727. (p) Parker, K. A.; Spero, D. M.; Van Epp, J. J. Org. Chem. 1988, 53, 4628. (q) Bartlett, P. A.; McLaren, K. L.; Ting, P. C. J. Am. Chem. Soc. 1988, 110, 1633. (r) Hart, D. J.; Seely, F. J. Am. Chem. Soc. 1988, 110, 1631. (s) Corey, E. J.; Pyne, S. G. Tetrahedron Lett. 1983, 24, 2821.
39. For previous work on both inter- and intramolecular free radical additions to oxime ethers, see: (a) Chiara, J. L.; Marco-Contelles, J.; Khair, N.; Gallego, P.; Destabel, C.; Bernabe, M. J. Org. Chem. 1995, 60, 6010. (b) Kiguchi, T.; Tajiri, K.; Ninomiya, I.; Naito, T. Tetrahedron Lett. 1995, 36, 253. (c) Naito, T.; Tajiri, K.; Harimoto, T.; Ninomiya, I.; Kiguchi, T. Tetrahedron Lett. 1994, 35, 2205. (d) Booth, S. E.; Jenkins, P. R.; Swain, C. J.; Sweeney, J. B.; J. Chem. Soc., Perkin Trans. 1 1994, 3499. (e) Parker, K.; Fokas, D. J. Org. Chem. 1994, 59, 3927. (f) Grissom, J. W.; Klingberg, D. J. Org. Chem. 1993, 58, 6559. (g) Pattenden, G.; Schulz, D. J. Tetrahedron Lett. 1993, 34, 6787. (h) Hatem, J.; Henriet-Bernard, C.; Grimaldi, J.; Maurin, R. Tetrahedron Lett. 1992, 33, 1057. (i) Marco-Contelles, J.; Pozuelo, C.; Jimeno, M. L.; Martinez, L.; Martinez-Grau, A. J. Org. Chem. 1992, 57, 2625. (j) Marco-Contelles, J.; Ruiz, P.; Sanchez, B.; Jimeno, M. L. Tetrahedron Lett. 1992, 33, 5261. (k) Parker, K. A.; Fokas, D. J. Am. Chem. Soc. 1992, 114, 9688. (l) Marco-Contelles, J.; Martinez, L.; Martinez-Grau, A.; Pozuelo, C.; Jimeno, M. L. Tetrahedron Lett. 1991, 32, 6437. (m) Booth, S. E.; Jenkins, P. R.; Swain, C. J. J. Chem. Soc., Chem. Commun. 1991, 1248. (n) Marco-Contelles, J.; Martinez, L.; Martinez- Grau, A. Tetrahedron: Asymmetry 1991, 2, 961. (o) Enholm, E. J.; Burnoff, J. A.; Jaramillo, L. M. Tetrahedron Lett. 1990, 31, 3727. (p) Parker, K. A.; Spero, D. M.; Van Epp, J. J. Org. Chem. 1988, 53, 4628. (q) Bartlett, P. A.; McLaren, K. L.; Ting, P. C. J. Am. Chem. Soc. 1988, 110, 1633. (r) Hart, D. J.; Seely, F. J. Am. Chem. Soc. 1988, 110, 1631. (s) Corey, E. J.; Pyne, S. G. Tetrahedron Lett. 1983, 24, 2821.
40. For previous work on both inter- and intramolecular free radical additions to oxime ethers, see: (a) Chiara, J. L.; Marco-Contelles, J.; Khair, N.; Gallego, P.; Destabel, C.; Bernabe, M. J. Org. Chem. 1995, 60, 6010. (b) Kiguchi, T.; Tajiri, K.; Ninomiya, I.; Naito, T. Tetrahedron Lett. 1995, 36, 253. (c) Naito, T.; Tajiri, K.; Harimoto, T.; Ninomiya, I.; Kiguchi, T. Tetrahedron Lett. 1994, 35, 2205. (d) Booth, S. E.; Jenkins, P. R.; Swain, C. J.; Sweeney, J. B.; J. Chem. Soc., Perkin Trans. 1 1994, 3499. (e) Parker, K.; Fokas, D. J. Org. Chem. 1994, 59, 3927. (f) Grissom, J. W.; Klingberg, D. J. Org. Chem. 1993, 58, 6559. (g) Pattenden, G.; Schulz, D. J. Tetrahedron Lett. 1993, 34, 6787. (h) Hatem, J.; Henriet-Bernard, C.; Grimaldi, J.; Maurin, R. Tetrahedron Lett. 1992, 33, 1057. (i) Marco-Contelles, J.; Pozuelo, C.; Jimeno, M. L.; Martinez, L.; Martinez-Grau, A. J. Org. Chem. 1992, 57, 2625. (j) Marco-Contelles, J.; Ruiz, P.; Sanchez, B.; Jimeno, M. L. Tetrahedron Lett. 1992, 33, 5261. (k) Parker, K. A.; Fokas, D. J. Am. Chem. Soc. 1992, 114, 9688. (l) Marco-Contelles, J.; Martinez, L.; Martinez-Grau, A.; Pozuelo, C.; Jimeno, M. L. Tetrahedron Lett. 1991, 32, 6437. (m) Booth, S. E.; Jenkins, P. R.; Swain, C. J. J. Chem. Soc., Chem. Commun. 1991, 1248. (n) Marco-Contelles, J.; Martinez, L.; Martinez- Grau, A. Tetrahedron: Asymmetry 1991, 2, 961. (o) Enholm, E. J.; Burnoff, J. A.; Jaramillo, L. M. Tetrahedron Lett. 1990, 31, 3727. (p) Parker, K. A.; Spero, D. M.; Van Epp, J. J. Org. Chem. 1988, 53, 4628. (q) Bartlett, P. A.; McLaren, K. L.; Ting, P. C. J. Am. Chem. Soc. 1988, 110, 1633. (r) Hart, D. J.; Seely, F. J. Am. Chem. Soc. 1988, 110, 1631. (s) Corey, E. J.; Pyne, S. G. Tetrahedron Lett. 1983, 24, 2821.
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