Polymethylhydrosiloxane (PMHS)/trifluoroacetic acid (TFA): a novel system for reductive amination reactions
摘要:
Polymethylhydrosiloxine (PMHS)/trifluoroacetic acid (TFA) was discovered as a novel metal-free system for reductive amination reactions. A variety of(het)aryl amines as well as a representative carbamate and urea were successfully alkylated by benzaldehyde in the presence of PMHS and TFA in dichloromethane at room temperature in moderate to excellent yields (28-87%). Furthermore, this reaction protocol was Successfully applied to the alkylation of p-nitroaniline with a wide range of aldehydes, ketones, and a representative acetal to obtain the alkylated products in yields ranging from 40% to 92%. The current work represents one of the very few examples of PMHS being activated by a Bronsted acid. (C) 2009 Elsevier Ltd. All rights reserved.