Aminoazanium of DABCO: An Amination Reagent for Alkyl and Aryl Pinacol Boronates

Abstract

The aminoazanium of DABCO (H₂ N-DABCO) has been developed as a general and practical amination reagent for the direct amination of alkyl and aryl pinacol boronates. This compound is stable and practical for use as a reagent. Various primary, secondary. and tertiary alkyl-Bpin and aryl-Bpin substrates were aminated to give the corresponding amine derivatives. The amination is stereospecific. The anti-Markovnikov hydroamination of olefins was easily achieved by catalytic hydroboration with HBpin and in subsequent situ amination using H₂ N-DABCO. Moreover, the combination of 1,2-diboration of olefins, using B₂ pin₂ , with this amination process achieved the unprecedented 1,2-diamination of olefins. The amination protocol was also successfully extended to aryl pinacol boronates.