Formation and evaluation of novel silica supported secondary amines via an effective ‘in-situ’ reduction of silica supported imines Original Research Article

An effective method for the reduction of silica supported imines has been developed. This represents a useful approach to the selective preparation of silica supported secondary amines. The resultant modifications have produced effective catalysts, which are more hydrolytically stable than the corresponding imines. There is a large spread of different activities in the resulting catalysts, some of which are considerably more active than the simple primary amine, aminopropylsilica (AMPS). The nature of the alkyl group introduced in this technique thus plays a critical role in the catalyst activity. The nitroxyl radical, tetramethylpiperidinyloxy (TEMPO) has also been attached using this methodology, indicating that this approach may be of use in selectively functionalising AMPS leading to a wide range of supported species, bound via a hydrolytically stable linkage.