CaltechAUTHORS
Published October 16, 1995 | Version public
Journal Article Metadata-only

Stereoselective Free-Radical Cycloaddition-Macrocyclization in Facile Synthesis of Trans-Cyclohexano-Fused 12-Membered Crown Thioethers

Creators

  • 1. ROR icon Russian Academy of Sciences
  • 2. ROR icon Moscow State University of Fine Chemical Technologies
  • 3. ROR icon A. N. Nesmeyanov Institute of Organoelement Compounds

Abstract

Homolytic cycloaddition of dithiols 1,2 derived from trans- and eis-1,2-cyclohexanediols to alkynes, induced by Pr3B-O2, offers an extremely simple approach to trans- and cis-cyclohexano-fused 12-membered crown thialactones 4a-c-7a-c. The reaction of trans-1 proceeds with pronounced remote 1,6-asymmetric induction to give predominantly (IS *, 6R *, 12S *)-4a–c, while cis-2 reacts nonstereoselectively. Basing on molecular mechanics calculations the stereoselectivity is rationalized as a result of entropy favored pathway of macrocyclization.

Additional Information

Copyright © 1995 Published by Elsevier. (Received in UK 27 June 1995; revsed 25 August 1995; accepted 1 September 1995) We are grateful to Mr R Fleming (The University of Nottingham, U.K ) for recording several NMR (400 MHz) spectra We thank the InternatIonal Science Foundation (Soros Foundation) (Grant MPL 000) and Russian Foundation of Fundamental Studies (Projects 93-03-18110 and 94-03-09296) for generous financial support E.I.T. also indebtedly thanks the Royal Society for the Kapitza Fellowship and Professor Gerald Pattenden for very helpful discussion on macrocyclization. Dedicated to Professor Nikolay S. Zefirnv on the occasion of his 60th birthday.

Additional details

Identifiers

Eprint ID
40886
Resolver ID
CaltechAUTHORS:20130821-160734712

Funding

International Science Foundation
MPL000
Russian Foundation for Fundamental Studies
93-03-18110
Russian Foundation for Fundamental Studies
94-03-09296
Royal Society

Dates

Created
2013-08-29
Created from EPrint's datestamp field
Updated
2021-11-10
Created from EPrint's last_modified field