Development of earth-abundant metal catalysts for carbon-boron and carbon-carbon bond forming reactions

Abstract

We have developed a Markovnikov-selective cobalt-catalysed hydroboration of alkenes with pinacolborane at ambient temperature, using a bench-stable bipyridyl-oxazoline catalyst tBuBPOCoCl2 and NaOtBu as the in situ activator. This strategy has been applied to a variety of electronically and sterically differentiated styrene derivatives, bearing a range of functional groups, to give the secondary boronic esters in both high yield and regioselectivity.

We have developed a manganese-catalysed homo-coupling of aryl-, alkenyl- and heterocyclic boronic acids across a range of electronically and sterically differentiated coupling partners.

This mild and operationally simple coupling reaction uses commercially available and inexpensive manganese(III) acetylacetonate, ethanol as the solvent, and air as the terminal oxidant. This represents the first-stage in developing a new manganese-catalysed cross-coupling reaction for the synthesis biaryl compounds.