5-exo-trig Versus 6-endo-trig cyclization of Alk-5-enoyl radicals: The role of one-carbon ring expansion

Chemistry - A European Journal

Volumn 3, Issue 3, 1997, Pages 376-387

  Chatgilialoglu, Chryssostomos ^a   Ferreri, Carla ^b   Lucarini, Marco ^c   Venturini, Alessandro ^a   Zavitsas, Andreas A ^d  

^a CNR   (Italy)

^b UNIVERSITY OF NAPLES FEDERICO II   (Italy)

^c UNIVERSITY OF BOLOGNA   (Italy)

^d LONG ISLAND UNIVERSITY   (United States)

Author keywords

ab initio calculations; cyclizations; cycloketones; radicals; ring expansions

Indexed keywords

EID: 0031004405     PISSN: 09476539     EISSN: None     Source Type: Journal    
DOI: 10.1002/chem.19970030309     Document Type: Article

References (133)

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34. For some other recent examples, see: a) H.-S. Dang, B. P. Roberts, J. Chem. Soc. Chem. Commun. 1996, 2201-2202; b) P. A. Evans, J. D. Roseman, L. T. Garber, J. Org. Chem. 1996, 61, 4880-4881; c) P. A. Evans, J. D. Roseman, ibid. 1996, 61, 2252-2253; d) P. A. Evans, J. D. Roseman, Tetrahedron Lett. 1995, 36, 31-34; e) J. H. Penn, F. Liu, J. Org. Chem. 1994, 59, 2608-2612; f) T. Punniyamurthy, B. Bhatia, J. Iqbal, ibid. 1994, 59, 850-853; g) V. Gupta, D. Kahne, Tetrahedron Lett. 1993, 34, 591-594; h) M. D. Bachi, E. Bosch, J. Org. Chem. 1992, 57, 4696-4705; i) C. E. Schwartz, D. P. Curran, J. Am. Chem. Soc. 1990, 112, 9272-9284; j) J. E. Forbes, S. Z. Zard, ibid. 1990, 112, 2034-2035; k) P. Delduc, C. Tailhan, S. Z. Zard, J. Chem. Soc. Chem. Commun. 1988, 308-310.
35. For some other recent examples, see: a) H.-S. Dang, B. P. Roberts, J. Chem. Soc. Chem. Commun. 1996, 2201-2202; b) P. A. Evans, J. D. Roseman, L. T. Garber, J. Org. Chem. 1996, 61, 4880-4881; c) P. A. Evans, J. D. Roseman, ibid. 1996, 61, 2252-2253; d) P. A. Evans, J. D. Roseman, Tetrahedron Lett. 1995, 36, 31-34; e) J. H. Penn, F. Liu, J. Org. Chem. 1994, 59, 2608-2612; f) T. Punniyamurthy, B. Bhatia, J. Iqbal, ibid. 1994, 59, 850-853; g) V. Gupta, D. Kahne, Tetrahedron Lett. 1993, 34, 591-594; h) M. D. Bachi, E. Bosch, J. Org. Chem. 1992, 57, 4696-4705; i) C. E. Schwartz, D. P. Curran, J. Am. Chem. Soc. 1990, 112, 9272-9284; j) J. E. Forbes, S. Z. Zard, ibid. 1990, 112, 2034-2035; k) P. Delduc, C. Tailhan, S. Z. Zard, J. Chem. Soc. Chem. Commun. 1988, 308-310.
36. For some other recent examples, see: a) H.-S. Dang, B. P. Roberts, J. Chem. Soc. Chem. Commun. 1996, 2201-2202; b) P. A. Evans, J. D. Roseman, L. T. Garber, J. Org. Chem. 1996, 61, 4880-4881; c) P. A. Evans, J. D. Roseman, ibid. 1996, 61, 2252-2253; d) P. A. Evans, J. D. Roseman, Tetrahedron Lett. 1995, 36, 31-34; e) J. H. Penn, F. Liu, J. Org. Chem. 1994, 59, 2608-2612; f) T. Punniyamurthy, B. Bhatia, J. Iqbal, ibid. 1994, 59, 850-853; g) V. Gupta, D. Kahne, Tetrahedron Lett. 1993, 34, 591-594; h) M. D. Bachi, E. Bosch, J. Org. Chem. 1992, 57, 4696-4705; i) C. E. Schwartz, D. P. Curran, J. Am. Chem. Soc. 1990, 112, 9272-9284; j) J. E. Forbes, S. Z. Zard, ibid. 1990, 112, 2034-2035; k) P. Delduc, C. Tailhan, S. Z. Zard, J. Chem. Soc. Chem. Commun. 1988, 308-310.
37. For some other recent examples, see: a) H.-S. Dang, B. P. Roberts, J. Chem. Soc. Chem. Commun. 1996, 2201-2202; b) P. A. Evans, J. D. Roseman, L. T. Garber, J. Org. Chem. 1996, 61, 4880-4881; c) P. A. Evans, J. D. Roseman, ibid. 1996, 61, 2252-2253; d) P. A. Evans, J. D. Roseman, Tetrahedron Lett. 1995, 36, 31-34; e) J. H. Penn, F. Liu, J. Org. Chem. 1994, 59, 2608-2612; f) T. Punniyamurthy, B. Bhatia, J. Iqbal, ibid. 1994, 59, 850-853; g) V. Gupta, D. Kahne, Tetrahedron Lett. 1993, 34, 591-594; h) M. D. Bachi, E. Bosch, J. Org. Chem. 1992, 57, 4696-4705; i) C. E. Schwartz, D. P. Curran, J. Am. Chem. Soc. 1990, 112, 9272-9284; j) J. E. Forbes, S. Z. Zard, ibid. 1990, 112, 2034-2035; k) P. Delduc, C. Tailhan, S. Z. Zard, J. Chem. Soc. Chem. Commun. 1988, 308-310.
38. For some other recent examples, see: a) H.-S. Dang, B. P. Roberts, J. Chem. Soc. Chem. Commun. 1996, 2201-2202; b) P. A. Evans, J. D. Roseman, L. T. Garber, J. Org. Chem. 1996, 61, 4880-4881; c) P. A. Evans, J. D. Roseman, ibid. 1996, 61, 2252-2253; d) P. A. Evans, J. D. Roseman, Tetrahedron Lett. 1995, 36, 31-34; e) J. H. Penn, F. Liu, J. Org. Chem. 1994, 59, 2608-2612; f) T. Punniyamurthy, B. Bhatia, J. Iqbal, ibid. 1994, 59, 850-853; g) V. Gupta, D. Kahne, Tetrahedron Lett. 1993, 34, 591-594; h) M. D. Bachi, E. Bosch, J. Org. Chem. 1992, 57, 4696-4705; i) C. E. Schwartz, D. P. Curran, J. Am. Chem. Soc. 1990, 112, 9272-9284; j) J. E. Forbes, S. Z. Zard, ibid. 1990, 112, 2034-2035; k) P. Delduc, C. Tailhan, S. Z. Zard, J. Chem. Soc. Chem. Commun. 1988, 308-310.
39. For some other recent examples, see: a) H.-S. Dang, B. P. Roberts, J. Chem. Soc. Chem. Commun. 1996, 2201-2202; b) P. A. Evans, J. D. Roseman, L. T. Garber, J. Org. Chem. 1996, 61, 4880-4881; c) P. A. Evans, J. D. Roseman, ibid. 1996, 61, 2252-2253; d) P. A. Evans, J. D. Roseman, Tetrahedron Lett. 1995, 36, 31-34; e) J. H. Penn, F. Liu, J. Org. Chem. 1994, 59, 2608-2612; f) T. Punniyamurthy, B. Bhatia, J. Iqbal, ibid. 1994, 59, 850-853; g) V. Gupta, D. Kahne, Tetrahedron Lett. 1993, 34, 591-594; h) M. D. Bachi, E. Bosch, J. Org. Chem. 1992, 57, 4696-4705; i) C. E. Schwartz, D. P. Curran, J. Am. Chem. Soc. 1990, 112, 9272-9284; j) J. E. Forbes, S. Z. Zard, ibid. 1990, 112, 2034-2035; k) P. Delduc, C. Tailhan, S. Z. Zard, J. Chem. Soc. Chem. Commun. 1988, 308-310.
40. For some other recent examples, see: a) H.-S. Dang, B. P. Roberts, J. Chem. Soc. Chem. Commun. 1996, 2201-2202; b) P. A. Evans, J. D. Roseman, L. T. Garber, J. Org. Chem. 1996, 61, 4880-4881; c) P. A. Evans, J. D. Roseman, ibid. 1996, 61, 2252-2253; d) P. A. Evans, J. D. Roseman, Tetrahedron Lett. 1995, 36, 31-34; e) J. H. Penn, F. Liu, J. Org. Chem. 1994, 59, 2608-2612; f) T. Punniyamurthy, B. Bhatia, J. Iqbal, ibid. 1994, 59, 850-853; g) V. Gupta, D. Kahne, Tetrahedron Lett. 1993, 34, 591-594; h) M. D. Bachi, E. Bosch, J. Org. Chem. 1992, 57, 4696-4705; i) C. E. Schwartz, D. P. Curran, J. Am. Chem. Soc. 1990, 112, 9272-9284; j) J. E. Forbes, S. Z. Zard, ibid. 1990, 112, 2034-2035; k) P. Delduc, C. Tailhan, S. Z. Zard, J. Chem. Soc. Chem. Commun. 1988, 308-310.
41. For some other recent examples, see: a) H.-S. Dang, B. P. Roberts, J. Chem. Soc. Chem. Commun. 1996, 2201-2202; b) P. A. Evans, J. D. Roseman, L. T. Garber, J. Org. Chem. 1996, 61, 4880-4881; c) P. A. Evans, J. D. Roseman, ibid. 1996, 61, 2252-2253; d) P. A. Evans, J. D. Roseman, Tetrahedron Lett. 1995, 36, 31-34; e) J. H. Penn, F. Liu, J. Org. Chem. 1994, 59, 2608-2612; f) T. Punniyamurthy, B. Bhatia, J. Iqbal, ibid. 1994, 59, 850-853; g) V. Gupta, D. Kahne, Tetrahedron Lett. 1993, 34, 591-594; h) M. D. Bachi, E. Bosch, J. Org. Chem. 1992, 57, 4696-4705; i) C. E. Schwartz, D. P. Curran, J. Am. Chem. Soc. 1990, 112, 9272-9284; j) J. E. Forbes, S. Z. Zard, ibid. 1990, 112, 2034-2035; k) P. Delduc, C. Tailhan, S. Z. Zard, J. Chem. Soc. Chem. Commun. 1988, 308-310.
42. For some other recent examples, see: a) H.-S. Dang, B. P. Roberts, J. Chem. Soc. Chem. Commun. 1996, 2201-2202; b) P. A. Evans, J. D. Roseman, L. T. Garber, J. Org. Chem. 1996, 61, 4880-4881; c) P. A. Evans, J. D. Roseman, ibid. 1996, 61, 2252-2253; d) P. A. Evans, J. D. Roseman, Tetrahedron Lett. 1995, 36, 31-34; e) J. H. Penn, F. Liu, J. Org. Chem. 1994, 59, 2608-2612; f) T. Punniyamurthy, B. Bhatia, J. Iqbal, ibid. 1994, 59, 850-853; g) V. Gupta, D. Kahne, Tetrahedron Lett. 1993, 34, 591-594; h) M. D. Bachi, E. Bosch, J. Org. Chem. 1992, 57, 4696-4705; i) C. E. Schwartz, D. P. Curran, J. Am. Chem. Soc. 1990, 112, 9272-9284; j) J. E. Forbes, S. Z. Zard, ibid. 1990, 112, 2034-2035; k) P. Delduc, C. Tailhan, S. Z. Zard, J. Chem. Soc. Chem. Commun. 1988, 308-310.
43. For some other recent examples, see: a) H.-S. Dang, B. P. Roberts, J. Chem. Soc. Chem. Commun. 1996, 2201-2202; b) P. A. Evans, J. D. Roseman, L. T. Garber, J. Org. Chem. 1996, 61, 4880-4881; c) P. A. Evans, J. D. Roseman, ibid. 1996, 61, 2252-2253; d) P. A. Evans, J. D. Roseman, Tetrahedron Lett. 1995, 36, 31-34; e) J. H. Penn, F. Liu, J. Org. Chem. 1994, 59, 2608-2612; f) T. Punniyamurthy, B. Bhatia, J. Iqbal, ibid. 1994, 59, 850-853; g) V. Gupta, D. Kahne, Tetrahedron Lett. 1993, 34, 591-594; h) M. D. Bachi, E. Bosch, J. Org. Chem. 1992, 57, 4696-4705; i) C. E. Schwartz, D. P. Curran, J. Am. Chem. Soc. 1990, 112, 9272-9284; j) J. E. Forbes, S. Z. Zard, ibid. 1990, 112, 2034-2035; k) P. Delduc, C. Tailhan, S. Z. Zard, J. Chem. Soc. Chem. Commun. 1988, 308-310.
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77. For some other examples where steps e and g in Scheme 2 were explicity assumed, see: a) J. E. Baldwin, R. M. Adlington, J. Robertson, Tetrahedron 1989, 45, 909-922; b) T. Inokuchi, M Tsuji, H. Kawafuchi, S. Torii, J. Org. Chem. 1991, 56, 5945-5948; c) M. T. Crimmins, C. M. Dudek, A. W.-H. Cheung, Tetrahedron Lett. 1992, 33, 181-184; d) W. R. Bowman, P. J. Westlake, Tetrahedron 1992, 48, 4027-4038.
78. For some other examples where steps e and g in Scheme 2 were explicity assumed, see: a) J. E. Baldwin, R. M. Adlington, J. Robertson, Tetrahedron 1989, 45, 909-922; b) T. Inokuchi, M Tsuji, H. Kawafuchi, S. Torii, J. Org. Chem. 1991, 56, 5945-5948; c) M. T. Crimmins, C. M. Dudek, A. W.-H. Cheung, Tetrahedron Lett. 1992, 33, 181-184; d) W. R. Bowman, P. J. Westlake, Tetrahedron 1992, 48, 4027-4038.
79. For some other examples where steps e and g in Scheme 2 were explicity assumed, see: a) J. E. Baldwin, R. M. Adlington, J. Robertson, Tetrahedron 1989, 45, 909-922; b) T. Inokuchi, M Tsuji, H. Kawafuchi, S. Torii, J. Org. Chem. 1991, 56, 5945-5948; c) M. T. Crimmins, C. M. Dudek, A. W.-H. Cheung, Tetrahedron Lett. 1992, 33, 181-184; d) W. R. Bowman, P. J. Westlake, Tetrahedron 1992, 48, 4027-4038.
80. a) Y. Ito, S. Fujii, T. Saegusa, J. Org. Chem. 1976, 41, 2073-2074;
81. b) Y. Ito, T. Sugaya, M. Nakatsuka, T. Saegusa, J. Am. Chem. Soc. 1977, 99, 8366-8367;
82. c) K. I. Booker-Milburn, Synlett 1992, 809-810;
83. d) K. I. Booker-Milburn, D. F. Thompson, ibid. 1993, 592-593.
84. A. Sommazzi, N. Cardi, F. Garbassi, C. Chatgilialoglu, U. S. Patent 5 369 187, 1994.
85. C. Chatgilialoglu, C. Ferreri, A. Sommazzi, J. Am. Chem. Soc. 1996, 118, 7223-7224.
86. For a review on the use of organosilanes in the Barton-McCombie deoxygenation reactions, see: C. Chatgilialoglu, C. Ferreri, Res. Chem. Intermed. 1993, 19, 755-775.
87. Identification by comparison with the retention time of authentic samples.
88. The diastereoisomerism is expected to be lost in the formation of the corresponding carbon-centered radical.
89. C. Chatgilialoglu, J. Dickhaut, B. Giese, J. Org. Chem. 1991, 56, 6399-6403.
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91. For reviews, see: a) M. Newcomb, Tetrahedron 1993, 49, 1151-1176; b) D. Griller, K. U. Ingold. Acc. Chem. Res. 1980, 13, 317-323.
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93. Compound 29 was obtained in an (E)/(Z) isomeric composition of 90/10.
94. 1H NMR is necessary after work-up. On the other hand, the eight products obtained from the reduction of compound 29 were well separated and easily determined in the crude reaction mixture using undecane as internal standard.
95. 3SnH was 0.75 M, (E)/(Z) ratios of 89/11, 88/12, 86/14, and 85/13 were obtained at 233, 256, 298, and 323 K, respectively.
96. C. Chatgilialoglu, M. Ballestri, C. Ferreri, D. Vecchi, J. Org. Chem. 1995, 60, 3826-3831.
97. -1 [9a].
98. -1 [9a].
99. GAUSSIAN 92; M. J. Frisch, M. Head-Gordon, J. B. Foresman, G. W. Trucks, K. Raghavachari, H. B. Schlegel, M. A. Robb, J. S. Binkley, C. Gonzalez, D. J. DeFrees, D. J. Fox, R. A. Whiteside, R. Seeger, C. F. Melius, J. Baker, L. R. Kahn, J. J. P. Stewart, E. M. Fluder, S. Topiol, J. A. Pople, Gaussian, Pittsburgh, PA, 1992.
100. -1, 1 → 3 is ΔH = -15.3, 2 → 3 is ΔH = -3.0, 42 → 43 is ΔH = -13.7, 42 → 44 is ΔH = -16.8, and 43 → 44 is ΔH = -3.1.
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106. -1 less stable than 45.
107. -1 (C1-C2 = 6.19 and C2-C3 = 4.94 Å), which is the value used here for the trans-hept-5-enoyl radical.
108. For 45, even though no local minimum appears in Figure 4 for such a structure, AM1 indicates the possibility of a metastable intermediate with a small barrier for decomposition, since the O-H bond in the corresponding alcohol can be stretched up to 6.00 Å without beta scission. It is only when the hydroxylic hydrogen is completely removed, or is removed in one step from the alcohol, that AM1 optimizes radical 45 to 44.
109. For recent discussions on the gem-dialkyl effect, see: a) M. E. Jung, Synlett, 1990, 186-190; b) M. E. Jung, J. Gervay, J. Am. Chem. Soc. 1991, 113, 224-232; c) A. L. Parrill, D. P. Dolata, Tetrahedron Lett. 1994, 35, 7319-7322; d) M. E. Jung, B. T. Vu, ibid. 1996, 37, 451-454.
110. For recent discussions on the gem-dialkyl effect, see: a) M. E. Jung, Synlett, 1990, 186-190; b) M. E. Jung, J. Gervay, J. Am. Chem. Soc. 1991, 113, 224-232; c) A. L. Parrill, D. P. Dolata, Tetrahedron Lett. 1994, 35, 7319-7322; d) M. E. Jung, B. T. Vu, ibid. 1996, 37, 451-454.
111. For recent discussions on the gem-dialkyl effect, see: a) M. E. Jung, Synlett, 1990, 186-190; b) M. E. Jung, J. Gervay, J. Am. Chem. Soc. 1991, 113, 224-232; c) A. L. Parrill, D. P. Dolata, Tetrahedron Lett. 1994, 35, 7319-7322; d) M. E. Jung, B. T. Vu, ibid. 1996, 37, 451-454.
112. For recent discussions on the gem-dialkyl effect, see: a) M. E. Jung, Synlett, 1990, 186-190; b) M. E. Jung, J. Gervay, J. Am. Chem. Soc. 1991, 113, 224-232; c) A. L. Parrill, D. P. Dolata, Tetrahedron Lett. 1994, 35, 7319-7322; d) M. E. Jung, B. T. Vu, ibid. 1996, 37, 451-454.
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