A novel generation of coupling reagents. Enantiodifferentiating coupling reagents prepared in situ from 2-chloro-4,6-dimethoxy-1,3,5-triazine (CDMT) and chiral tertiary amines

Z J Kamiński; B Kolesińska; J E Kamińska; J Góra

doi:10.1021/jo0101499

A novel generation of coupling reagents. Enantiodifferentiating coupling reagents prepared in situ from 2-chloro-4,6-dimethoxy-1,3,5-triazine (CDMT) and chiral tertiary amines

J Org Chem. 2001 Sep 21;66(19):6276-81. doi: 10.1021/jo0101499.

Authors

Z J Kamiński¹, B Kolesińska, J E Kamińska, J Góra

Affiliation

¹ Institute of Organic Chemistry and Institute of General Food Chemistry, Technical University of Łódź, ul. Zeromskiego 116, 90-924 Łódź, Poland. kaminsz@ck-sg.p.lodz.pl

PMID: 11559174
DOI: 10.1021/jo0101499

Abstract

Coupling of racemic N-protected amino acids with amino components by means of 2-chloro-4,6-dimethoxy-1,3,5-triazine (CDMT) in the presence of chiral tertiary amines such as strychnine, brucine, and sparteine proceeds enantioselectively, affording appropriate amides or dipeptides in 69-85% yield. The configuration of the preferred enantiomer and enantiomeric enrichment depend on the structures of the amine and carboxylic acid. Calculated Kagan enantioselectivity parameters (s) are in the range 1.6-195. Chiral triazinylammonium chlorides formed in situ from CDMT and chiral tertiary amines are postulated as reactive intermediates involved in the process of enantioselective activation of N-protected amino acids.