THE CHROMIUM-REFORMATSKY REACTION - ANTI-SELECTIVE EVANS-TYPE ALDOL REACTIONS WITH EXCELLENT INVERSE INDUCTION AT AMBIENT-TEMPERATURE

Authors
GABRIEL T WESSJOHANN L
Citation
T. Gabriel et L. Wessjohann, THE CHROMIUM-REFORMATSKY REACTION - ANTI-SELECTIVE EVANS-TYPE ALDOL REACTIONS WITH EXCELLENT INVERSE INDUCTION AT AMBIENT-TEMPERATURE, Tetrahedron letters, 38(25), 1997, pp. 4387-4388
Citations number
17
Categorie Soggetti
Chemistry Inorganic & Nuclear
Journal title
Tetrahedron letters → ACNP
ISSN journal
00404039
Volume
38
Issue
25
Year of publication
1997
Pages
4387 - 4388
Database
ISI
SICI code
0040-4039(1997)38:25<4387:TCR-AE>2.0.ZU;2-9
Abstract
anti-Aldol products are available in a two step, one pot reaction of 4 -substituted oxazolidone, 2-bromopropionyl halide, chromium dichloride and an aldehyde. The diastereofacial selection (induction) is opposit e to those of boron Evans enolates, i.e. the unusual ''non-Evans'' ant i-aldol products are formed in excellent excess and yield - without ba se and at room temperature. In contrast to our previous assumptions al pha-unsubstituted acetyloxazolidones do give the Evans-type beta-anti- products preferentially. (C) 1997 Elsevier Science Ltd.