The manganese-catalyzed hydrosilylation and hydroboration of alkenes has been developed using a single manganese(II) precatalyst and reaction protocol. Both reactions proceed with excellent control of regioselectivity and in high yields across a variety of sterically and electronically differentiated substrates (25 examples). Alkoxide activation, using NaO Bu, was key to precatalyst activation and reactivity. Catalysis was achieved across various functional groups and on gram-scale for both the developed methodologies with catalysts loadings as low as 0.5 mol %.

A one-pot Au(I)-catalyzed reaction cascade to multi-ring heterocyclic products from alkynoic acids and primary amines is reported. The gold catalyst initially primes the alkynoic acid, via cyclization to an enol lactone, to react with a primary amine tethered to an electron rich heteroaromatic system. Then, via postulated Lewis acid assisted acidity, the Au(I) catalyst activates the amido ketone intermediate to undergo an N-acyl iminium ion cyclization. The reaction sequence is simple to perform, efficient, and broad in its scope to a diverse range of complex heterocyclic products.

A mutually compatible and cooperative combination of copper(I) triflate and bifunctional 9-amino-9-deoxyepicinchona-derived urea compounds for the enantioselective Conia-ene cyclization of alkyne-tethered beta-ketoester substrates is reported. The reaction is efficient, broad in scope, and easy to perform and allows access to chiral methylenecyclopentane products with high enantiocontrol. The transformation illustrates the concept of combining inactive precatalysts with inactive transition-metal-ion complexes in situ to reversibly create a catalytically active combination of the two.

A one-pot, multistep reaction cascade to cyclopentenes from alpha,beta-unsaturated ketones and propargylated carbon acids through a combination of organocatalysis and transition metal ion catalysis is reported; the reaction cascade is simple to perform, occurs under mild conditions and is broad in scope.

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