Synthesis of pyridine functionalized NHC Iron(II) complexes and their applications

Abstract

Catalytic hydroboration of carbonyl compounds using pinacolborane is an important technique for synthesizing organoboranes and for synthesizing corresponding alcohols in organic chemistry. There is always a quest of better performing catalysts. N-heterocyclic carbene (NHC) based transition metal complexes have shown their great potential in this field. Herein, we present a facile synthesis of Iron(II) complexes of pincer based pyridine functionalized N-heterocyclic carbene, which are successfully characterized by SCXRD analysis and multinuclear NMR spectroscopy. This easily prepared iron catalysts enables hydroboration of aromatic aldehydes with HBpin (pinacolborane) without any additive. The hydroboration reaction gives good yield with low catalyst loading (1-2 mol%) at room temperature and shows wide range of functional group tolerance.