Radical addition of ethers to terminal alkynes with high E-selectivity

European Journal of Organic Chemistry

Volumn , Issue 30, 2009, Pages 5146-5152

  Chen, Ziii ^a   Zhang, Yu Xin ^b   An, Yan ^a   Song, Xin Li ^a   Wang, Ya Hui ^a   Zhu, Li Li ^a   Guo, Lin ^b  

^a RENMIN UNIVERSITY OF CHINA   (China)

^b BEIHANG UNIVERSITY   (China)

Author keywords

Hydrogen abstraction ; Radical reactions ; Radicals ; Vinylzinc

Indexed keywords

EID: 70350145695     PISSN: 1434193X     EISSN: 10990690     Source Type: Journal    
DOI: 10.1002/ejoc.200900858     Document Type: Article

References (81)

1. For reviews, see: a) C. L. Hill, Activation and Functionalization of Alkanes, Academic Press, New York, 1989;
2. b) A. E. Shilov, G. B. Shul'pin, Chem. Rev. 1997, 97, 2879;
3. c) G. Dyker, Angew. Chem. Int. Ed, 1999, 38, 1699;
4. d) F. Jossey, D. Kefirt, J. Sorba, Free Radicals in Organic Chemistry, John Wiley & Sons, Masson, 1995, pp. 211-220.
5. 2Zn see: a) K. Yamada, H. Fujihara, Y. Yamamoto, Y. Miwa, T. Taga, K. Tomioka, Org. Lett. 2002, 4, 3509;
6. b) K. Yamada, Y. Yamamoto, K. Tomioka, Org. Lett. 2003, 5, 1797;
7. c) K. Yamada, Y. Yamamoto, M. Maekawa, K. Tomioka, J. Org. Chem. 2004, 64, 1531;
8. d) Y. Yamamoto, K. Yamada, K. Tomioka, Tetrahedron Lett. 2004, 45, 795;
9. e) Y. Yamamoto, M. Maekawa, T. Akindele, K. Yamada, K. Tomioka, Tetrafiedron 2005, 61, 379;
10. f) T. Akindele, Y. Yamamoto, M. Maekawa, H. Umeki, K. Yamada, K. Tomioka, Org. Lett. 2006, 8, 5729;
11. g) K. Yamada, H. Umeki, M. Maekawa, Y. Yamamoto, T. Akindele, M. Nakano, K. Tomioka, Tetrahedron 2008, 64, 7258;
12. h) Review: K. Yamada, Y. Yamamoto, K. J. Tomioka, Synth. Org. Chem. Jpn. 2004, 62, 1158;
13. 3B see:
14. j) T. Yoshimitsu, Y. Arano, H. Nagaoka, J. Org. Chem. 2005, 70, 2342;
15. k) T. Yoshimitsu, M. Tsunoda, H. Nagaoka, Chem. Commun. 1999, 1745.
16. For some examples of generating the a-alkoxyalkyl radicals by other methods, see: a) J. Gong, P. L. Fuchs, J. Am. Chem. Soc. 1996, 118, 4486;
17. b) J. Xiang, P. L. Fuchs, J. Am. Chem. Soc. 1996, 118, 11986;
18. c) J. Xiang, W. Jiang, J. Gong, P. L. Fuchs, J. Am. Chem. Soc. 1997, 119, 4123;
19. d) K. Hirao, S. Sakaguchi, Y. Ishii, Tetrahedron Lett. 20022C 43, 3617;
20. e) S. Kim, N. Kim, W-J. Chung, C. H. Cho, Synlett 2001, 937;
21. f) M. Fernandez, R. Alonso, Org. Lett. 2003, 5, 2461;
22. g) S. Torrente, R. Alonso, Org. Lett. 2001, 3, 1985;
23. h) R. L. Jacobs, G. G. Ecke, J. Org. Chem. 1963, 28, 3036;
24. i) R. Mosca, M. Fagnoni, M. Mella, A. Albini, Tetrahedron 2001, 57, 10319;
25. j) J. Chen, R. L. Kirchmeier, J. M. Shreeve, Inorg. Chem. 1996, 35, 6676;
26. k) A. Clerici, R. Cannella, N. Pastori, W. Panzeri, O. Porta, Tetraliedron 2006, 62, 5986;
27. Z.-Q. Liu, L. Sun, J.-G. Wang, J. Han, Y-K. Zhao, B. Zhou, Org. Lett. 2009, 11, 1437.
28. For a recent report on dialkylzinc-mediated radical reactions, see: a) A. Pérez-Luna, C. Botuha, F. Ferreira, F. Chemla, Chem. Eur. J. 2008, 14, 8784;
29. b) L. Feray, M. P. Bertrand, Eur. J. Org. Chem. 2008, 3164.
30. 2-Vinyl-substituted ethers have been the goal of numerous synthetic efforts, see: a) T. Kawashima, M. Nakamura, N. Inamoto, Phosphorus Sulfur Silicon Relat. Elem. 1992, 69, 293;
31. b) T. Kawashima, M. Nakamura, N. Inamoto, Heterocycles 1997, 44, 487;
32. c) I. Kadota, L. M. Lutete, A. Shibuya, Y. Yamamoto, Tetrahedron Lett. 2001, 42, 6207;
33. d) A. J. Clark, S. Rooke, T. J. Sparey, P. C. Taylor, Tetrahedron Lett. 1996, 37, 909;
34. e) Y-J. Jang, Y-K. Shih, J.-Y. Liu, W-Y. Kuo, C-F. Yao, Chem. Eur. J. 2003, 9, 2123;
35. f) Y.-h. Zhang, C-J. Li, Tetrahedron Lett. 2004, 45, 7581.
36. For reviews on stereocontrol in radical reaction, see: a) D. P. Curran, N. A. Porter, B. Giese, Stereochemistry of Radical Reactions, VCH, Weinheim, Germany, 1995;
37. b) N. A. Porter, B. Giese, D. P. Curran, Acc. Chem. Res. 1991, 24, 296;
38. c) P. Renaud, M. Gerster, Angew. Chem. Int. Ed. 1998, 37, 2562;
39. d) T. V. RajanBabu, Acc. Chem. Res. 1991, 24, 139;
40. e) W. Smadja, Synlett 1994, 1;
41. f) M. P. Sibi, S. Manyem, J. Zimmerman, Chem. Rev. 2003, 103, 3263;
42. g) M. P. Sibi, N. A. Porter, Acc. Chem. Res. 1999, 32, 163;
43. h) M. P. Sibi, S. Manyem, Tetrahedron 2000, 56, 8033.
44. a) For Lewis acids in radical reactions, see: P. Renaud, M. Gerster, Angew. Chem. Int. Ed. 1998, 37, 2562;
45. b) Lewis-acidic properties of dialkylzinc: S. Bazin, L. Feray, M. P. Bertrand, Chimia 2006, 60, 260.
46. 3-hybrized C atoms by vinyl radicals are very scarce. For a few examples of intramolecular hydrogen abstraction see: a) R. C. Neuman, G. D. Holmes, J. Org. Chem 1966, 33, 4317;
47. b) P. G. Webb, J. A. Kampmeier, J. Am. Chem. Soc. 1971, 93, 3730;
48. c) R. M. Kopchk, J. A. Kampmeier, J. Am. Chem. Soc. 1968, 90, 6733;
49. d) E. I. Heiba, R. M. Dessau, J. Am. Chem. Soc. 1967, 89, 3772;
50. e) R. M. Wilson, T. J. Commons, J. Org. Chem. 1975,40,2891.
51. a) J. K. Crandall, W. J. Michaely, J. Org. Chem. 1984, 49, 4244;
52. b) P. K. Mandai, G. Maiti, S. C. Roy, J. Org. Chem. 1998, 63, 2829;
53. c) J. Tang, H. Shinokubo, K. Oshima, Tetrahedron 1999, 55, 1893;
54. d) M. Okabe, M. Abe, M. Tada, J. Org. Chem. 1982, 47, 1775;
55. e) R. Yanada, Y. Koh, N. Nishimori, A. Matsumura, S. Obika, H. Mitsuya, N. Fujii, Y. Takemoto, J. Org. Chem. 2004, 69, 2417;
56. f) A. Blum, W. Hess, A. Studer, Synthesis 2004, 2226;
57. g) B. C. Ranu, T. Mandai, Tetrahedron Lett. 2006, 47, 2859.
58. α-Alkoxyl radicals are nucleophilic reactants; a) B. Giese, An gew. Chem. Int. Ed. Engl. 1983, 22, 753;
59. b) B. Giese, Angew. Chem. Int. Ed. Engl. 1985, 24, 553.
60. 2 was added to the system in order to accelerate the reaction.
61. Although intermediate B can be stabilized by the electron-withdrawing groups, the effect of different substitution on E/Z selectivity is still unclear.
62. 2Zn.
63. Position 2 in 1,3-dioxane is much more reactive than position 4: a) V. Malatesta, K. U. Ingold, J. Am. Chem. Soc. 1981, 103, 609;
64. b) A. L. J. Beckwith, C. J. Easton, J. Am. Chem. Soc. 1981, 103, 615.
65. Intermediate C can be decomposed by oxygen gas. Keeping the reaction mixture in the dry air for 30 min, most of the formed product was decomposed.
66. Alkyne 1 can not be consumed to the completion, might because of the zinc-proton exchange of alkyne 1 with intermediate C, or with Me2Zn; a) T. M. Bertrand, G. Courtois, L. Migniniac, Tetrahedron Lett. 1974, 15, 3147;
67. b) M. Nakamura, T. Fujimoto, K. Endo, E. Nakamura, Org. Lett. 2004, 6, 4837.
68. Hydrogen abstraction by vinyl radical has been reported before, in which other hydrogen source such as alkylzinc peroxides has been proposed; see ref. [4].
69. Ring size effects on alkyl radical reactivity: P. J. Kropp, J. Am. Chem. Soc. 1969, 91, 5783.
70. A small amount of E/Z-3b were also detected in the reaction mixture. See Supporting Information.
71. For reviews on Negishi coupling: a) E.-I. Negishi, J. Organomet. Chem. 2002, 34, 653;
72. b) E.-I. Negishi, Acc. Chem. Res. 1982, 15, 340.
73. This reaction can not be quenched by D2O.
74. 8]THF.
75. Me2Zn/O2 system was also tested, but no Z-isomer was obtained; see Supporting Information.
76. B. Giese, Angew. Chem. 1989, 101, 993;
77. Angew. Chem. Int. Ed. Engl. 1989, 28, 969.
78. 2-isomeric radicals (going through an sp intermediate). For some examples of highly Z-selective radical additions, see: a) B. A. Trofimov, N. K. Gusarova, S. N. Arbuzova, N. I. Ivanova, A. V. Artem'ev, P. A. Volkov, I. A. Ushakov, S. F. Malysheva, V. A. Kuimov, J. Organomet. Chem. 2009, 694, 677;
79. b) B. A. Trofimov, S. F. Malysheva, N. K. Gusarova, N. A. Belogorlova, S. F. Vasilevsky, V. B. Kobychev, B. G. Sukhov, I. A. Ushakov, Mendeleev Commun. 2007, 17, 181;
80. c) K. Miura, K. Oshima, K. Utimoto, Bull. Chem. Soc. Jpn. 1993, 66, 2356;
81. d) M. B. Faraoni, V. I. Dodero, J. C. Podesta, ARKIVOC 2005, 88.