Synlett 2004(6): 1054-1058  
DOI: 10.1055/s-2004-822895
LETTER
© Georg Thieme Verlag Stuttgart · New York

Intramolecular Chromium(II)-Catalyzed Pinacol Cross Coupling of 2-Methylene-α,ω-dicarbonyls [1]

Ulrich Groth*, Marc Jung, Till Vogel
Fachbereich Chemie, Universität Konstanz, Fach M-720, Universitätsstr. 10, 78457 Konstanz, Germany
Fax: +49(7531)884155; e-Mail: Ulrich.Groth@uni-konstanz.de;
Further Information

Publication History

Received 11 February 2004
Publication Date:
25 March 2004 (online)

Abstract

Using only 10% of CrCl2 as catalyst, manganese-powder as reducing agent and TMSCl as scavenger, 2-methylene-α,ω-di­aldehydes and -ketones can be coupled to form cyclic diols dia­stereoselectively. The diastereomeric excess strongly depends on the ring size and the substituents of the ω-carbonyl group. The greater the ring size the higher diastereoselectivities are observed. In all cases cis-diols are preferentially formed.