Design and synthesis of a new organocatalyst and its application to the asymmetric synthesis of tandem Michael/Henry reaction and aldol reactio

A novel organocatalytic asymmetric domino Michael/Henry reaction of nitroalkene and pentane-1,5-dial (generated in situ) in aqueous media has been developed by using diarylprolinol silyl ether with benzoic acid as a water-soluble organocatalyst. The catalyst was converted to ionic liquid supported catalyst to give highly functionalized cyclohexanes with four stereogenic centers in excellent enantioselectivities (>99% ee). This catalyst can be recycled for seven times with slight reduction in activity and selectivity. An effective primary amine organocatalysts was designed and then used to catalyze the direct asymmetric syn-aldol reactions of various aromatic aldehydes and hydroxy acetone with moderate to high selectivity.