Alkene Difunctionalization Directed by Free Amines: Diamine Synthesis via Nickel-Catalyzed 1,2-Carboamination

A versatile
method to access differentially substituted 1,3- and
1,4-diamines via nickel-catalyzed three-component 1,2-carboamination
of alkenyl amines with aryl/alkenylboronic ester nucleophiles and
N–O electrophiles is reported. The reaction proceeds efficiently
with free primary and secondary amines without needing a directing
auxiliary or protecting group and is enabled by fine-tuning the leaving
group on the N–O reagent. The transformation is highly regioselective
and compatible with a wide range of coupling partners and alkenyl
amine substrates, all performed at room temperature. A series of kinetic
studies support a mechanism in which alkene coordination to the nickel
catalyst is turnover-limiting.