Enantioselective Acyloin Rearrangement of Acyclic Aldehydes Catalyzed by Chiral Oxazaborolidinium Ion.

Org Lett

Department of Chemistry, Sungkyunkwan University, 300 Cheoncheon, Jangan, Suwon 16419, Korea.

Published: February 2021

AI Article Synopsis

  • A new method for the catalytic enantioselective acyloin rearrangement of acyclic aldehydes is presented, allowing for the production of highly optically active acyloin derivatives.
  • In the reaction, a chiral oxazaborolidinium ion catalyst is used, resulting in chiral α-hydroxy aryl ketones with yields as high as 95% and enantioselectivities up to 98% ee.
  • The method also successfully rearranges α,α-dialkyl-α-siloxy aldehydes into chiral α-siloxy alkyl ketones, achieving yields of up to 92% and good enantioselectivity (up to 89% ee).

Article Abstract

A catalytic enantioselective acyloin rearrangement of acyclic aldehydes to synthesize highly optically active acyloin derivatives is described. In the presence of a chiral oxazaborolidinium ion catalyst, the reaction provided chiral α-hydroxy aryl ketones in high yield (up to 95%) and enantioselectivity (up to 98% ee). In addition, the enantioselective acyloin rearrangement of α,α-dialkyl-α-siloxy aldehydes produced chiral α-siloxy alkyl ketones in high yield (up to 92%) with good enantioselectivity (up to 89% ee).

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http://dx.doi.org/10.1021/acs.orglett.1c00314DOI Listing

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