Kinetic resolution of nitrogen heterocycles with a reusable polymer-supported reagent.

Shake it up baby! Simply shaking a polymer-supported reagent and the racemic amine at room temperature kinetically resolves a broad range of N-heterocycles with good selectivity. The polymer-supported reagents are robust, easy to regenerate, and can be reused dozens of times. Cleavable acyl groups can be used to give access to both amine enantiomers in a single resolution.

Expanded substrate scope and catalyst optimization for the catalytic kinetic resolution of N-heterocycles.

The scope, reactivity, and selectivity of the chiral hydroxamic acid-catalyzed kinetic resolution of chiral amines are improved by a new catalyst structure and a more environmentally friendly reaction protocol. In addition to increasing selectivity across all substrates, these conditions make possible the resolution of N-heterocycles containing lactams or other basic functional groups that can inhibit the catalyst.

Catalytic kinetic resolution of cyclic secondary amines.

The catalytic resolution of racemic cyclic amines has been achieved by an enantioselective amidation reaction featuring an achiral N-heterocyclic carbene catalyst and a new chiral hydroxamic acid cocatalyst working in concert. The reactions proceed at room temperature, do not generate nonvolatile byproducts, and provide enantioenriched amines by aqueous extraction.

Asymmetric synthesis of tertiary and quaternary allyl- and crotylsilanes via the borylation of lithiated carbamates.

Tertiary allyl- or crotylsilanes have been prepared in high er and dr via the lithiation-borylation reaction of alkyl carbamates with silaboronates. Using a related strategy, quaternary allylsilanes could be accessed in similarly high er.