The traceless Petasis borono‐Mannich reaction of enals, sulfonylhydrazines, and allylboronates, catalyzed by chiral biphenols, results in an asymmetric reductive transposition of the in situ generated allylic diazene. Acyclic 1,4‐diene products bearing either alkyl‐ or aryl‐substituted benzylic stereocenters are afforded in excellent yields and enantiomeric ratios of up to 99:1. The use of crotylboronates in the reaction results in concomitant formation of two stereocenters in either a 1,4‐
- Award ID(s):
- 1856437
- PAR ID:
- 10500148
- Publisher / Repository:
- American Chemical Society
- Date Published:
- Journal Name:
- Journal of the American Chemical Society
- Volume:
- 145
- Issue:
- 36
- ISSN:
- 0002-7863
- Page Range / eLocation ID:
- 19642 to 19654
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract The traceless Petasis borono‐Mannich reaction of enals, sulfonylhydrazines, and allylboronates, catalyzed by chiral biphenols, results in an asymmetric reductive transposition of the in situ generated allylic diazene. Acyclic 1,4‐diene products bearing either alkyl‐ or aryl‐substituted benzylic stereocenters are afforded in excellent yields and enantiomeric ratios of up to 99:1. The use of crotylboronates in the reaction results in concomitant formation of two stereocenters in either a 1,4‐
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