Manganese-catalysed hydrofunctionalisation of alkenes

Abstract

The development of new first-row transition metal catalysts as both replacements for precious metals catalysts and in the search for novel reactivity is a crucial evolution for catalysis. Manganese is a non-toxic, inexpensive and Earth-abundant metal, making it a perfect candidate for catalysis. Despite this, manganese catalysis has not undergone the same development as for other Earth-abundant metals. The manganese-catalysed hydrosilylation and hydroboration of alkenes has been developed to give hydrofunctionalisation products in typically good yields (up to >95%) with control of regio- and chemo-selectivity. This work uses a bench-stable precatalyst/ activator manifold allowing for a simple methodology, ideal for the nonspecialist. This represents the first example of a developed methodology for the manganesecatalysed hydrosilylation of alkenes. This methodology uses a bis(imino)pyridine manganese(II) pre-catalyst which has previously been unreactive in related reactions. The critical discovery has been in the use of an alkoxide activation system which enables the generation of a catalytically-active manganese species.