Chair/twist-boat energy gap in monocyclic, conformationally unconstrained polyalkylcyclohexanes

Journal of Organic Chemistry

Volumn 61, Issue 23, 1996, Pages 8277-8284

  Weiser, Jörg ^a   Golan, Oren ^b   Fitjer, Lutz ^a   Biali, Silvio E ^b  

^a UNIVERSITY OF GÖTTINGEN   (Germany)

^b HEBREW UNIVERSITY OF JERUSALEM   (Israel)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 0001380433     PISSN: 00223263     EISSN: None     Source Type: Journal    
DOI: 10.1021/jo961526y     Document Type: Article

References (71)

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2. (b) Anderson, J. E. in The Chemistry of Alkanes and Cycloalkanes; Patai, S., Rappoport, Z., Eds.; Wiley: Chichester, 1992; Chapter 3.
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4. (d) Eliel, E. L.; Wilen, S. H. Stereochemistry of Organic Compounds; Wiley: New York, 1994; Chapter 11. For a review on conformationally flexible molecules see: Hoffmann, R. W. Angew. Chem., Int. Ed. Engl. 1992, 31, 1124.
5. (d) Eliel, E. L.; Wilen, S. H. Stereochemistry of Organic Compounds; Wiley: New York, 1994; Chapter 11. For a review on conformationally flexible molecules see: Hoffmann, R. W. Angew. Chem., Int. Ed. Engl. 1992, 31, 1124.
6. (a) For a review on nonchair conformations of cyclohexane see: Kellie, G. M.; Riddell, F. G. Top. Stereochem. 1974, 8, 225.
7. (b) The TB form of cyclohexane has been trapped at low temperatures: Squillacote, M.; Sheridan, R. S.; Chapman, O. L.; Anet, F. A. L. J. Am. Chem. Soc. 1975, 97, 3244. For a vibrational analysis of the TB form see: Offenbach, J. L.; Fredin, L.; Strauss, H. L. J. Am. Chem. Soc. 1981, 103, 1001.
8. (b) The TB form of cyclohexane has been trapped at low temperatures: Squillacote, M.; Sheridan, R. S.; Chapman, O. L.; Anet, F. A. L. J. Am. Chem. Soc. 1975, 97, 3244. For a vibrational analysis of the TB form see: Offenbach, J. L.; Fredin, L.; Strauss, H. L. J. Am. Chem. Soc. 1981, 103, 1001.
9. The boat form is a transition state between TB forms. For a review on the pseudorotation of the TB form see: Strauss, H. L. Ann. Rev. Phys. Chem. 1983, 34, 301.
10. Mohler, D. L.; Vollhardt, K. P. C.; Wollf, S. Angew. Chem., Int. Ed. Engl. 1990, 29, 1151. For a review on planar cyclohexyl rings see: Dodziuk, H. Modern Conformational Analysis; VCH Publishers: New York, 1995; p 163.
11. Mohler, D. L.; Vollhardt, K. P. C.; Wollf, S. Angew. Chem., Int. Ed. Engl. 1990, 29, 1151. For a review on planar cyclohexyl rings see: Dodziuk, H. Modern Conformational Analysis; VCH Publishers: New York, 1995; p 163.
12. Perhydrophenalene: Dillen, J. L. M. J. Org. Chem. 1984, 49, 3800. Perhydrophenanthrene: Allinger, N. L.; Gordon, B. J.; Tymisky, I. J.; Wuesthoff, M. T. J. Org. Chem. 1971, 36, 739. Allinger, N. L.; Honig, H.; Burkert, U.; Asolnai, L.; Huttner, G. Tetrahedron 1984, 40, 3449. Perhydroanthracene: Allinger, N. L., Wuesthoff, M. T. J. Org. Chem. 1971, 36, 2051. Vanhee, P.; van de Graaf, B.; Baas, J. M. A.; Tavernier, D. Tetrahedron Lett. 1982, 23, 3837. Vanhee, P.; van de Graaf, B.; Tavernier, D.; Baas, J. M. A. J. Org. Chem. 1983, 48, 648.
13. Perhydrophenalene: Dillen, J. L. M. J. Org. Chem. 1984, 49, 3800. Perhydrophenanthrene: Allinger, N. L.; Gordon, B. J.; Tymisky, I. J.; Wuesthoff, M. T. J. Org. Chem. 1971, 36, 739. Allinger, N. L.; Honig, H.; Burkert, U.; Asolnai, L.; Huttner, G. Tetrahedron 1984, 40, 3449. Perhydroanthracene: Allinger, N. L., Wuesthoff, M. T. J. Org. Chem. 1971, 36, 2051. Vanhee, P.; van de Graaf, B.; Baas, J. M. A.; Tavernier, D. Tetrahedron Lett. 1982, 23, 3837. Vanhee, P.; van de Graaf, B.; Tavernier, D.; Baas, J. M. A. J. Org. Chem. 1983, 48, 648.
14. Perhydrophenalene: Dillen, J. L. M. J. Org. Chem. 1984, 49, 3800. Perhydrophenanthrene: Allinger, N. L.; Gordon, B. J.; Tymisky, I. J.; Wuesthoff, M. T. J. Org. Chem. 1971, 36, 739. Allinger, N. L.; Honig, H.; Burkert, U.; Asolnai, L.; Huttner, G. Tetrahedron 1984, 40, 3449. Perhydroanthracene: Allinger, N. L., Wuesthoff, M. T. J. Org. Chem. 1971, 36, 2051. Vanhee, P.; van de Graaf, B.; Baas, J. M. A.; Tavernier, D. Tetrahedron Lett. 1982, 23, 3837. Vanhee, P.; van de Graaf, B.; Tavernier, D.; Baas, J. M. A. J. Org. Chem. 1983, 48, 648.
15. Perhydrophenalene: Dillen, J. L. M. J. Org. Chem. 1984, 49, 3800. Perhydrophenanthrene: Allinger, N. L.; Gordon, B. J.; Tymisky, I. J.; Wuesthoff, M. T. J. Org. Chem. 1971, 36, 739. Allinger, N. L.; Honig, H.; Burkert, U.; Asolnai, L.; Huttner, G. Tetrahedron 1984, 40, 3449. Perhydroanthracene: Allinger, N. L., Wuesthoff, M. T. J. Org. Chem. 1971, 36, 2051. Vanhee, P.; van de Graaf, B.; Baas, J. M. A.; Tavernier, D. Tetrahedron Lett. 1982, 23, 3837. Vanhee, P.; van de Graaf, B.; Tavernier, D.; Baas, J. M. A. J. Org. Chem. 1983, 48, 648.
16. Perhydrophenalene: Dillen, J. L. M. J. Org. Chem. 1984, 49, 3800. Perhydrophenanthrene: Allinger, N. L.; Gordon, B. J.; Tymisky, I. J.; Wuesthoff, M. T. J. Org. Chem. 1971, 36, 739. Allinger, N. L.; Honig, H.; Burkert, U.; Asolnai, L.; Huttner, G. Tetrahedron 1984, 40, 3449. Perhydroanthracene: Allinger, N. L., Wuesthoff, M. T. J. Org. Chem. 1971, 36, 2051. Vanhee, P.; van de Graaf, B.; Baas, J. M. A.; Tavernier, D. Tetrahedron Lett. 1982, 23, 3837. Vanhee, P.; van de Graaf, B.; Tavernier, D.; Baas, J. M. A. J. Org. Chem. 1983, 48, 648.
17. Perhydrophenalene: Dillen, J. L. M. J. Org. Chem. 1984, 49, 3800. Perhydrophenanthrene: Allinger, N. L.; Gordon, B. J.; Tymisky, I. J.; Wuesthoff, M. T. J. Org. Chem. 1971, 36, 739. Allinger, N. L.; Honig, H.; Burkert, U.; Asolnai, L.; Huttner, G. Tetrahedron 1984, 40, 3449. Perhydroanthracene: Allinger, N. L., Wuesthoff, M. T. J. Org. Chem. 1971, 36, 2051. Vanhee, P.; van de Graaf, B.; Baas, J. M. A.; Tavernier, D. Tetrahedron Lett. 1982, 23, 3837. Vanhee, P.; van de Graaf, B.; Tavernier, D.; Baas, J. M. A. J. Org. Chem. 1983, 48, 648.
18. Intramolecular hydrogen bonds may stabilize TB conformers. Stolow, R. D.; McDonagh, P. M.; Bonaventura, M. M. J. Am. Chem. Soc. 1984, 86, 2165. Stolow, R. D. J. Am. Chem. Soc. 1961, 83, 2592.
19. Intramolecular hydrogen bonds may stabilize TB conformers. Stolow, R. D.; McDonagh, P. M.; Bonaventura, M. M. J. Am. Chem. Soc. 1984, 86, 2165. Stolow, R. D. J. Am. Chem. Soc. 1961, 83, 2592.
20. 1,2-Di-tert-butylcyclohexane: van der Graaf, B.; van Bekkum, H.; Wepster, B. M.; Recl. Trav. Chim. Pays-Bas 1968, 87, 777. Kessler, H.; Gusowsky, V.; Hanack, M. Tetrahedron Lett. 1968, 4665. van der Graaf, B.; van Bekkum, H.; van Koningsveld, H.; Sinnema, A.; van Veen, A.; Wepster, B. M.; van Wijk, A. M. Recl. Trav. Chim. Pays-Bas 1974, 93, 135.
21. 1,2-Di-tert-butylcyclohexane: van der Graaf, B.; van Bekkum, H.; Wepster, B. M.; Recl. Trav. Chim. Pays-Bas 1968, 87, 777. Kessler, H.; Gusowsky, V.; Hanack, M. Tetrahedron Lett. 1968, 4665. van der Graaf, B.; van Bekkum, H.; van Koningsveld, H.; Sinnema, A.; van Veen, A.; Wepster, B. M.; van Wijk, A. M. Recl. Trav. Chim. Pays-Bas 1974, 93, 135.
22. 1,2-Di-tert-butylcyclohexane: van der Graaf, B.; van Bekkum, H.; Wepster, B. M.; Recl. Trav. Chim. Pays-Bas 1968, 87, 777. Kessler, H.; Gusowsky, V.; Hanack, M. Tetrahedron Lett. 1968, 4665. van der Graaf, B.; van Bekkum, H.; van Koningsveld, H.; Sinnema, A.; van Veen, A.; Wepster, B. M.; van Wijk, A. M. Recl. Trav. Chim. Pays-Bas 1974, 93, 135.
23. 1,3-Di-tert-butylcyclohexane: (a) Allinger, N. L.; Freiberg, L. A. J. Am. Chem. Soc. 1960, 82, 2393. (b) Remijnse, J. D.; van Bekkum, H.; Wepster, B. M. Recl. Trav. Chim. Pays-Bas 1974, 93, 93.
24. 1,3-Di-tert-butylcyclohexane: (a) Allinger, N. L.; Freiberg, L. A. J. Am. Chem. Soc. 1960, 82, 2393. (b) Remijnse, J. D.; van Bekkum, H.; Wepster, B. M. Recl. Trav. Chim. Pays-Bas 1974, 93, 93.
25. 1,4-Di-tert-butylcyclohexane: (a) van Bekkum, H.; Hoefnagel, M. A.; de Lavieter, L.; van Veen, A.; Verkade, P. E.; Wemmers, A.; Wepster, B. M.; Palm, J. H.; Schäfer, L.; Dekker, H.; Mosselman, C.; Somsen, G. Recl. Trav. Chim. Pays-Bas 1968, 87, 1363. See also ref 8b. (b)For an electron diffraction study of cis-1,4-di-tert-butylcyclohexane see: Schubert, W. K.; Southern, J. F.; Schäfer, L. J. Mol. Struct. 1973, 16, 403.
26. 1,4-Di-tert-butylcyclohexane: (a) van Bekkum, H.; Hoefnagel, M. A.; de Lavieter, L.; van Veen, A.; Verkade, P. E.; Wemmers, A.; Wepster, B. M.; Palm, J. H.; Schäfer, L.; Dekker, H.; Mosselman, C.; Somsen, G. Recl. Trav. Chim. Pays-Bas 1968, 87, 1363. See also ref 8b. (b)For an electron diffraction study of cis-1,4-di-tert-butylcyclohexane see: Schubert, W. K.; Southern, J. F.; Schäfer, L. J. Mol. Struct. 1973, 16, 403.
27. For calculations of di-tert-butylcyclohexanes see: (a)Allinger, N. L.; Hirsch, J. A.; Miller, M. A.; Tyminsky, I. J.; Van-Catledge, F. A. J. Am. Chem. Soc. 1968, 90, 1199. (b) Askari, M.; Merrifield, D. L.; Schäfer, L. Tetrahedron Lett. 1976, 3497. (c) van de Graaf, B.; Baas, J. M. A.; Wepster, B. M. Rec. Trav. Chim. Pays Bas 1978, 97, 268. (d) Unwalla, R. J., Profeta, S., Jr; Cartledge, F. K. J. Org. Chem. 1988, 53, 5658.
28. For calculations of di-tert-butylcyclohexanes see: (a)Allinger, N. L.; Hirsch, J. A.; Miller, M. A.; Tyminsky, I. J.; Van-Catledge, F. A. J. Am. Chem. Soc. 1968, 90, 1199. (b) Askari, M.; Merrifield, D. L.; Schäfer, L. Tetrahedron Lett. 1976, 3497. (c) van de Graaf, B.; Baas, J. M. A.; Wepster, B. M. Rec. Trav. Chim. Pays Bas 1978, 97, 268. (d) Unwalla, R. J., Profeta, S., Jr; Cartledge, F. K. J. Org. Chem. 1988, 53, 5658.
29. For calculations of di-tert-butylcyclohexanes see: (a)Allinger, N. L.; Hirsch, J. A.; Miller, M. A.; Tyminsky, I. J.; Van-Catledge, F. A. J. Am. Chem. Soc. 1968, 90, 1199. (b) Askari, M.; Merrifield, D. L.; Schäfer, L. Tetrahedron Lett. 1976, 3497. (c) van de Graaf, B.; Baas, J. M. A.; Wepster, B. M. Rec. Trav. Chim. Pays Bas 1978, 97, 268. (d) Unwalla, R. J., Profeta, S., Jr; Cartledge, F. K. J. Org. Chem. 1988, 53, 5658.
30. For calculations of di-tert-butylcyclohexanes see: (a)Allinger, N. L.; Hirsch, J. A.; Miller, M. A.; Tyminsky, I. J.; Van-Catledge, F. A. J. Am. Chem. Soc. 1968, 90, 1199. (b) Askari, M.; Merrifield, D. L.; Schäfer, L. Tetrahedron Lett. 1976, 3497. (c) van de Graaf, B.; Baas, J. M. A.; Wepster, B. M. Rec. Trav. Chim. Pays Bas 1978, 97, 268. (d) Unwalla, R. J., Profeta, S., Jr; Cartledge, F. K. J. Org. Chem. 1988, 53, 5658.
31. (a) Fitjer, L.; Scheuermann, H. J.; Klages, U.; Wehle, D.; Stephenson, D. S.; Binsch, G. Chem. Ber. 1986, 119, 1144.
32. (b) Traetteberg, M.; Bakken, P.; Seip, R.; Fitjer, L.; Scheuermann, H. J. J. Mol. Struct. 1987, 159, 325.
33. (c) Aped, P.; Allinger, N. L. J. Am. Chem. Soc. 1992, 114, 1.
34. For other spirosubstituted systems with populated twist-boat conformations see: Fitjer, L.; Klages, U; Kühn, W.; Stephenson, D. S.; Binsch, G.; Noltemeyer, M.; Egert, E.; Sheldrick, G. M. Tetrahedron 1984, 21, 4337.
35. (a) For an early review on MM calculations of the chair/TB energy gap see ref 2a.
36. (b) For reviews on molecular mechanics calculations of cyclohexanes see: Osawa, E.; Varnali, T. in ref 1c, Chapter 4, p 137.
37. (c) For a review on ab initio studies of cyclohexane rings see: Cremer, D.; Szabo, K. J. in ref 1c, Chapter 3, p 59.
38. (d) For early molecular mechanics calculations of the chair/TB energy gap see: Hendrickson, J. B. J. Am. Chem. Soc. 1981, 83, 4537. Wiberg, K. B.; Boyd, R. H. J. Am. Chem. Soc. 1972, 94, 8426.
39. (d) For early molecular mechanics calculations of the chair/TB energy gap see: Hendrickson, J. B. J. Am. Chem. Soc. 1981, 83, 4537. Wiberg, K. B.; Boyd, R. H. J. Am. Chem. Soc. 1972, 94, 8426.
40. Golan, O.; Goren, Z.; Biali, S. E. J. Am. Chem. Soc. 1990, 112, 9300.
41. Allinger, N. L. MM3(92), Technical Utilization Corporation. Allinger, N. L.; Yuh, Y. H.; Lii, J.-H. J. Am. Chem. Soc. 1989, 111, 8551. For a description of the older MM2 program see: Allinger, N. L. J. Am. Chem. Soc. 1977, 99, 8127.
42. Allinger, N. L. MM3(92), Technical Utilization Corporation. Allinger, N. L.; Yuh, Y. H.; Lii, J.-H. J. Am. Chem. Soc. 1989, 111, 8551. For a description of the older MM2 program see: Allinger, N. L. J. Am. Chem. Soc. 1977, 99, 8127.
43. Allinger, N. L. MM3(92), Technical Utilization Corporation. Allinger, N. L.; Yuh, Y. H.; Lii, J.-H. J. Am. Chem. Soc. 1989, 111, 8551. For a description of the older MM2 program see: Allinger, N. L. J. Am. Chem. Soc. 1977, 99, 8127.
44. Weiser, J.; Holthausen, M. C.; Fitjer, L. Submitted for publication. HUNTER may be obtained from QCPE, University of Indiana, Bloomington, IN 47405.
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46. Kirkpatrick, S.; Gelatt, C. D., Jr.; Vecchi, M. P. Science 1983, 220, 671. For applications to molecular mechanics see: Wilson, S. R.; Cui, W.; Moskowitz, J. W.; Schmidt, K. E. Tetrahedron Lett. 1988, 29, 4373. Wilson, S. R.; Cui, W.; Moskowitz, J. W.; Schmidt, K. E. J. Comput. Chem, 1991, 12, 342. Guarnieri, F.; Wilson, S. R. Tetrahedron 1992, 48, 4271. Morley, S. D.; Jackson, D. E.; Saunders, M. R.; Vinter, J. G. J. Comput. Chem. 1992, 13, 693.
47. Kirkpatrick, S.; Gelatt, C. D., Jr.; Vecchi, M. P. Science 1983, 220, 671. For applications to molecular mechanics see: Wilson, S. R.; Cui, W.; Moskowitz, J. W.; Schmidt, K. E. Tetrahedron Lett. 1988, 29, 4373. Wilson, S. R.; Cui, W.; Moskowitz, J. W.; Schmidt, K. E. J. Comput. Chem, 1991, 12, 342. Guarnieri, F.; Wilson, S. R. Tetrahedron 1992, 48, 4271. Morley, S. D.; Jackson, D. E.; Saunders, M. R.; Vinter, J. G. J. Comput. Chem. 1992, 13, 693.
48. Kirkpatrick, S.; Gelatt, C. D., Jr.; Vecchi, M. P. Science 1983, 220, 671. For applications to molecular mechanics see: Wilson, S. R.; Cui, W.; Moskowitz, J. W.; Schmidt, K. E. Tetrahedron Lett. 1988, 29, 4373. Wilson, S. R.; Cui, W.; Moskowitz, J. W.; Schmidt, K. E. J. Comput. Chem, 1991, 12, 342. Guarnieri, F.; Wilson, S. R. Tetrahedron 1992, 48, 4271. Morley, S. D.; Jackson, D. E.; Saunders, M. R.; Vinter, J. G. J. Comput. Chem. 1992, 13, 693.
49. Kirkpatrick, S.; Gelatt, C. D., Jr.; Vecchi, M. P. Science 1983, 220, 671. For applications to molecular mechanics see: Wilson, S. R.; Cui, W.; Moskowitz, J. W.; Schmidt, K. E. Tetrahedron Lett. 1988, 29, 4373. Wilson, S. R.; Cui, W.; Moskowitz, J. W.; Schmidt, K. E. J. Comput. Chem, 1991, 12, 342. Guarnieri, F.; Wilson, S. R. Tetrahedron 1992, 48, 4271. Morley, S. D.; Jackson, D. E.; Saunders, M. R.; Vinter, J. G. J. Comput. Chem. 1992, 13, 693.
50. Goto, H.; Osawa, E. J. Am. Chem. Soc. 1989, 111, 8950.
51. Ivanov, P. M. J. Chem. Res., Miniprint 1986, 1173.
52. Fitjer, L.; Scheuermann, H.-J. ; Wehle, D. Tetrahedron Lett. 1984, 25, 2329. Wehle, D.; Scheuermann, H. J.; Fitjer, L. Chem. Ber. 1986, 119, 3127. For molecular mechanics calculations on the system see: Ermer, O.; Ivanov, P. M.; Osawa, E. J. Comput. Chem. 1985, 6, 401. According to the calculations the chair form of dodecamethylcyclohexane is more flattened and more flexible than the one of cyclohexane.
53. Fitjer, L.; Scheuermann, H.-J. ; Wehle, D. Tetrahedron Lett. 1984, 25, 2329. Wehle, D.; Scheuermann, H. J.; Fitjer, L. Chem. Ber. 1986, 119, 3127. For molecular mechanics calculations on the system see: Ermer, O.; Ivanov, P. M.; Osawa, E. J. Comput. Chem. 1985, 6, 401. According to the calculations the chair form of dodecamethylcyclohexane is more flattened and more flexible than the one of cyclohexane.
54. Fitjer, L.; Scheuermann, H.-J. ; Wehle, D. Tetrahedron Lett. 1984, 25, 2329. Wehle, D.; Scheuermann, H. J.; Fitjer, L. Chem. Ber. 1986, 119, 3127. For molecular mechanics calculations on the system see: Ermer, O.; Ivanov, P. M.; Osawa, E. J. Comput. Chem. 1985, 6, 401. According to the calculations the chair form of dodecamethylcyclohexane is more flattened and more flexible than the one of cyclohexane.
55. van Koningsveld, H. Acta Crystallogr. 1973, B29, 1214.
56. van Bekkum, H.; Buurmans, H. M. A.; van Minnen-Pathuis, G.; Wepster, B. M. Recl. Trav. Chim. Pays-Bas 1969, 88, 779.
57. Early MM calculations have also predicted a chair conformation for 13a. Schmidt, H. G.; Jaeschke, A.; Friebolin, H.; Kabuss, S.; Mecke, R. Org. Magn. Reson. 1969, 1, 163. Friebolin, H.; Schmidt, H. G.; Kabuss, S.; Faisst, W. Org. Magn. Reson. 1969, 1, 147.
58. Early MM calculations have also predicted a chair conformation for 13a. Schmidt, H. G.; Jaeschke, A.; Friebolin, H.; Kabuss, S.; Mecke, R. Org. Magn. Reson. 1969, 1, 163. Friebolin, H.; Schmidt, H. G.; Kabuss, S.; Faisst, W. Org. Magn. Reson. 1969, 1, 147.
59. Some of these systems were also calculated using the older MM2 program. We found consistently that the calculated relative stability of the TB form is larger using MM2 than using MM3.
60. all-cis-1,2,3,4,5,6-Hexamethylcyclohexane has been shown to exist in a chair conformation. Werner, H.; Mann, G.; Mühlstädt, M.; Köhler, H.-J. Tetrahedron Lett. 1970, 3563.
61. (a) Columbus, I.; Cohen, S.; Biali, S. E. J. Am. Chem. Soc. 1994, 116, 10306.
62. (b) Columbus, I.; Hoffmann, R. E.; Biali, S. E. J. Am. Chem. Soc. 1996, 118, 6890.
63. The configuration of a 1,2,4,5-tetrasubstituted system will be described by the method commonly used for fused-ring cyclohexanes. The mutual disposition of two vicinal groups will be denoted as "cis" or "trans". If the two substituents at the 2 and 4 positions are in a mutual cis or trans relationship, this will be denoted by the "syn" and "anti" descriptors, respectively.
64. Golan, O.; Biali, S. E. Unpublished results.
65. -1. See: Corey, E. J.; Feiner, N. F. J. Org. Chem. 1980, 45, 765.
66. Immirzi, A.; Torti, E. Atti Accad. Naz. Lincei, Cl. Sci. Fis. Mat. Nat. Rend. 1968, 44, 98.
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70. Anderson, J. E. J. Chem. Soc., Perkin Trans. 2 1992, 1343. Anderson, J. E.; Watson, D. G. J. Am. Chem. Soc. 1992, 114, 1517. Anderson, J. E.; Tocher, D. A.; Corrie, J. E. T.; Lunazzi, L. J. Am. Chem. Soc. 1993, 115, 3494.
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