학술논문

Design and Synthesis of a New Type of Ferrocene-Based Planar Chiral DMAP Analogues. A New Catalyst System for Asymmetric Nucleophilic Catalysist.
Document Type
Article
Source
Journal of Organic Chemistry. 10/14/2005, Vol. 70 Issue 21, p8332-8337. 6p. 11 Diagrams.
Subject
*CATALYSTS
*CHEMICAL inhibitors
*NUCLEOPHILIC reactions
*CHEMICAL reactions
*PYRIDINE
*HETEROCYCLIC compounds
Language
ISSN
0022-3263
Abstract
A new first-generation catalyst system for nucleophilic catalysis has been developed. It is based on a planar chiral ferrocene skeleton with either the potent nucleophile 4-(dimethylamino)pyridine (DMAP) or the related 4-nitropyridine N-oxide attached in either the 2- or the 3-position. The syntheses are short, efficient, and enantioselective and X-ray crystal structures of both DMAP-derived catalysts are presented. The DMAP-based catalysts were tested in asymmetric reactions and the 3-derivative 14 showed good activity and a moderate level of enantioselectivity. The sense of induction (selectivity) was studied using molecular modeling and the results pointed at new directions for future generations of catalysts based on this design. [ABSTRACT FROM AUTHOR]