Highly Ecient One-Pot Three-Component Mannich Reaction Under Solvent-Free Conditions

Authors

1 Research Center,University of Tehran

2 Department of Chemistry,Sharif University of Technology

Abstract

A mild and practically-convenient one-pot procedure for the direct Mannich reaction has
been developed using a condensation of amines, aldehydes and unmodi ed ketones under solvent free
conditions in the presence of ZnI2 with good to excellent yields. The present methodology o ers several
advantages, such as excellent yields, simple procedures, short reaction times and milder conditions with
very small amounts of catalyst. Furthermore, it is the rst time that the catalytic activity of several
catalysts under solvent free conditions has been studied. It was found that both the diastereoselectivity
and the rate of reaction were improved with various Lewis acids and metal oxides. However, the chiral
catalysts, such as L-cystine, (-)-cinchonidine and L-proline, did not work well in terms of yield and
diastereoselectivity under this condition.

Keywords