Dedicated to Prof. George A. Olah on the occasion of his receipt of the 2005 Priestley Medal. Support of our work by the “Hundreds Talent Program” from the Chinese Academy of Sciences is gratefully acknowledged.
Facile Synthesis of Chiral α-Difluoromethyl Amines from N-(tert-Butylsulfinyl)aldimines†
Article first published online: 8 SEP 2005
Copyright © 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Angewandte Chemie International Edition
Volume 44, Issue 36, pages 5882–5886, September 12, 2005
How to Cite
Li, Y. and Hu, J. (2005), Facile Synthesis of Chiral α-Difluoromethyl Amines from N-(tert-Butylsulfinyl)aldimines. Angew. Chem. Int. Ed., 44: 5882–5886. doi: 10.1002/anie.200501769
- Issue published online: 8 SEP 2005
- Article first published online: 8 SEP 2005
- Manuscript Received: 23 MAY 2005
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- 7We would like to thank one of the referees for the comment that the difluoromethyl functionality (CF2H) is isosteric to a carbinol (CH2OH) rather than a hydroxyl group (OH).
- 13Tetrahedron Lett. 1978, 19, 5225., ,
- 18Compared with aldehydes and ketones, imines (even activated N-tert-butanesulfinyl imines) generally display lower reactivity toward nucleophiles. Thus the stability and nucleophilicity of a proper nucleophile are crucial for its reactions with sulfinyl imines. For example, owing to the lower stability of in situ generated CF3− ion, the trifluoromethylation reactions of sulfinyl imines are very sensitive to the precursors of the CF3− ion and different reaction conditions. See ref. , and for a recent report see: J. Org. Chem. 2005, 70, 4741., ,
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- 20N-(tert-butylsulfinyl)aldimine was chosen for its higher electrophilicity relative to normal unactivated imines and, more importantly, for its potential as a chiral auxiliary. For details about its preparation, see:
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