Novel carbohydrate-derived prolinamide as a highly efficient, recoverable catalyst for direct aldol reactions in water

The catalytic activity of novel carbohydrate-derived prolinamide in the enantioselective aldol reactions has been examined for the first time. The organocatalyst 2b was found to be an efficient organocatalyst for the asymmetric aldol reaction in water. This organocatalyst is applicable to the reactions of a wide range of aromatic aldehydes with cyclic and acyclic ketones in high yields (up to 98%). These reactions exhibit high anti/syn ratios (up to 99%) and excellent enantioselectivities (up to 99%). Importantly, the catalyst can be easily recovered and recycled with only a slight decrease in enantioselectivity after five cycles. Crown Copyright (C) 2012 Published by Elsevier B.V. All rights reserved.