Enantioselective free radical reactions

Accounts of Chemical Research

Volumn 32, Issue 2, 1999, Pages 163-171

  Sibi, Mukund P ^a   Porter, Ned A ^b,c  

^a NORTH DAKOTA STATE UNIVERSITY   (United States)

^b DUKE UNIVERSITY   (United States)

^c VANDERBILT UNIVERSITY   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

FREE RADICAL;

ALKYLATION; CHEMICAL REACTION; CHEMICAL STRUCTURE; COMPLEX FORMATION; CONFORMATION; CONFORMATIONAL TRANSITION; REVIEW; STEREOCHEMISTRY;

EID: 0032960346     PISSN: 00014842     EISSN: None     Source Type: Journal    
DOI: 10.1021/ar9600547     Document Type: Review

References (57)

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8. (b) Evans, D. A.; Miller, S. J.; Lectka, T. Bis(oxazoline)-Copper(II) Complexes as Chiral Catalysts for the Enantioselective Diels - Alder Reaction. J. Am. Chem. Soc. 1993, 115, 6460-6461.
9. 2 - Symmetric Chiral Bis(oxazoline)-Fe(III) Complex. J. Am. Chem. Soc. 1991, 113, 728-729.
10. See: Eliel, E. L.; Wilen, S. H.; Mander, L. N. Stereochemistry of Organic Compounds; Wiley-Interscience: New York, 1994; pp 835-845. Radical displacement at chiral phosphorus has been demonstrated by Bentrude; see: Bentrude, W. G.; Moriyama, M.; Mueller, H.-D.; Sopchick, A. E. The Reactions of Ethoxy Radicals with Optically Active Tertiary Phosphines. Stereochemistry of the Substitution Process and the Question of Permutation Modes for the Possible Phophoranyl Radical Intermediates. J. Am. Chem. Soc. 1983, 105, 6053-6061. Bentrude, W. G. Phosphoranyl Radicals: Their Structure, formation, and Reactions. Acc. Chem. Res. 1982, 15, 117-125.
11. See: Eliel, E. L.; Wilen, S. H.; Mander, L. N. Stereochemistry of Organic Compounds; Wiley-Interscience: New York, 1994; pp 835-845. Radical displacement at chiral phosphorus has been demonstrated by Bentrude; see: Bentrude, W. G.; Moriyama, M.; Mueller, H.-D.; Sopchick, A. E. The Reactions of Ethoxy Radicals with Optically Active Tertiary Phosphines. Stereochemistry of the Substitution Process and the Question of Permutation Modes for the Possible Phophoranyl Radical Intermediates. J. Am. Chem. Soc. 1983, 105, 6053-6061. Bentrude, W. G. Phosphoranyl Radicals: Their Structure, formation, and Reactions. Acc. Chem. Res. 1982, 15, 117-125.
12. See: Eliel, E. L.; Wilen, S. H.; Mander, L. N. Stereochemistry of Organic Compounds; Wiley-Interscience: New York, 1994; pp 835-845. Radical displacement at chiral phosphorus has been demonstrated by Bentrude; see: Bentrude, W. G.; Moriyama, M.; Mueller, H.-D.; Sopchick, A. E. The Reactions of Ethoxy Radicals with Optically Active Tertiary Phosphines. Stereochemistry of the Substitution Process and the Question of Permutation Modes for the Possible Phophoranyl Radical Intermediates. J. Am. Chem. Soc. 1983, 105, 6053-6061. Bentrude, W. G. Phosphoranyl Radicals: Their Structure, formation, and Reactions. Acc. Chem. Res. 1982, 15, 117-125.
13. See ref 1a, pp 216-220.
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16. There have been several reports on the use of Lewis acids to affect the course of free radical cyclizations. See, for example: (a) Feldman, K. S.; Romanelli, A. L.; Ruckle, R. E.; Miller, R. F. Cyclopentane Synthesis via Free-Radical-Mediated Addition of Functionalized Alkenes to Substituted Vinylcyclopropanes. J. Am. Chem. Soc. 1988, 110, 3300-3302.
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29. See, for example, Nicolas, E.; Russel, K. C.; Hruby, V. J. Asymmetric 1,4-Addition of Organocuprates to Chiral α,β-Unsaturated N - Acyl-4-phenyl-2-oxazolidinones: A New Approach to the Synthesis of Chiral β-Branched Carboxylic Acids. J. Org. Chem. 1993, 58, 766-770.
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35. The reaction of 31 with complexed 26 as well as the reaction of an uncomplexed radical with complexed 26 would not be favorable because of polar effects.
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37. Tin Lewis acids have been shown to affect product chemo- and stereoselectivity in cyclizations of oxazolidinone derivatives; see: Sibi, M. P.; Ji, J. Participation of Organotin Lewis Acids in Radical Reactions: Manipulation of Rotamer Population in N-Enoyloxazolidinones. J. Am. Chem. Soc. 1996, 118, 3063.
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