Showing posts with label MANNICH. Show all posts
Showing posts with label MANNICH. Show all posts

Friday 12 December 2014

Direct Catalytic Enantio- and Diastereoselective Mannich Reaction of Isocyanoacetates and Ketimines




http://onlinelibrary.wiley.com/doi/10.1002/anie.201309719/abstract

Abstract

A catalytic asymmetric synthesis of imidazolines with a fully substituted β-carbon atom by a Mannich-type addition/cyclization reaction of isocyanoacetate pronucleophiles and N-diphenylphosphinoyl ketimines has been developed. When a combination of a cinchona-derived aminophosphine precatalyst and silver oxide was employed as a binary catalyst system, good reactivity, high diastereoselectivities (up to 99:1 d.r.), and excellent enantioselectivities (up to 99 % ee) were obtained for a range of substrates.



Angewandte Chemie International Edition

Volume 53Issue 13pages 3462–3465March 24, 2014

Direct Catalytic Enantio- and Diastereoselective Mannich Reaction of Isocyanoacetates and Ketimines

  1. Dr. Irene Ortín and
  2. Prof. Dr. Darren J. Dixon*
Article first published online: 24 FEB 2014
DOI: 10.1002/anie.201309719

Abstract


A catalytic asymmetric synthesis of imidazolines with a fully substituted β-carbon atom by a Mannich-type addition/cyclization reaction of isocyanoacetate pronucleophiles and N-diphenylphosphinoyl ketimines has been developed. When a combination of a cinchona-derived aminophosphine precatalyst and silver oxide was employed as a binary catalyst system, good reactivity, high diastereoselectivities (up to 99:1 d.r.), and excellent enantioselectivities (up to 99 % ee) were obtained for a range of substrates.



Author Information

  1. Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Mansfield Road, Oxford OX1 3TA (UK)
*Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Mansfield Road, Oxford OX1 3TA (UK)===

Professor Darren J. Dixon


Department of Chemsitry








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