Comprehensive study on the effect of acid additives in 1(R),2(R)-Bis[(S)-prolinamido]cyclohexane catalyzed direct asymmetric aldol reactions in aqueous media
Title | Comprehensive study on the effect of acid additives in 1(R),2(R)-Bis[(S)-prolinamido]cyclohexane catalyzed direct asymmetric aldol reactions in aqueous media |
Publication Type | Journal Article |
Year of Publication | 2015 |
Authors | Bhowmick, S, Kunte, SS, Bhowmick, KC |
Journal | Indian Journal of Chemistry Section B-Organic Chemistry Including Medicinal Chemistry |
Volume | 54 |
Issue | 1 |
Pagination | 84-92 |
Date Published | JAN |
ISSN | 0376-4699 |
Keywords | acid additives, aqueous media, Asymmetric synthesis, direct aldol reaction, organocatalysis |
Abstract | The catalytic efficacy of (1R,2R)-bis[(S)-prolinamido]cyclohexane 1, prepared from the readily available natural amino acid L-proline has been studied for the direct asymmetric aldol reaction of cyclohexanone with substituted benzaldehydes at room temperature in presence of various acid additives. A wide variety of acids e.g. aliphatic fatty acid, chiral acid, sulphonic acid, aromatic acid, etc. have been used as additive for the aldol reaction in aqueous media. A loading of 10 mol% of catalyst 1 is employed in this reaction, and good yields (up to 98% yield), diastereoselectivity (up to 96% de) and enantioselectivities (up to 87% ee) can be achieved in aqueous media within very short reaction time (1-4 hours). |
Type of Journal (Indian or Foreign) | Indian |
Impact Factor (IF) | 0.471 |