Use of an efficient polystyrene-supported cerium catalyst for one-pot multicomponent synthesis of spiro-piperidine derivatives and click reactions in green solvent

摘要

One-pot multicomponent reactions are very demanding in synthetic organic chemistry. Here we report a new polystyrene-supported cerium catalyst (PS-Ce-amtp) obtained via an easy two-step procedure, which was thoroughly characterized using various techniques. PS-Ce-amtp catalyses the environmentally benign one-pot multicomponent synthesis of spiro-piperidine derivatives through the reaction of substituted aniline, cyclic active methylene compound and formaldehyde at room temperature. The catalyst also exhibits excellent catalytic activity in one-pot synthesis of 1,4-disubstituted 1,2,3-triazoles via click reaction between in situ generated azides (derived from anilines and amines) and terminal alkynes. The catalyst can be recovered easily after reaction and reused five times without significant loss in its catalytic activity. The advantageous features of this catalyst are atom economy, operational simplicity, short reaction times, easy handling and high recycling efficiency.