Dehydrogenative Diboration of Alkynes Catalyzed by Ir/CO/tBuNC System

Catalytic dehydrogenative diboration (DHDB) of alkyne with HBpin was achieved using [Ir(COD)Cl](2) and other related Ir precursors under CO atmosphere. The selectivity for DHDB over hydroboration was higher in less polar solvents and under higher CO pressure. It was further improved when catalytic amount of tBuNC was added to the reaction. It was possible to achieve DHDB of both terminal and internal alkynes with selectivity for DHDB of up to 9:1 under the best conditions. Some DHDB products were isolated on the preparative scale. (C) 2020 Elsevier B.V. All rights reserved.

Automated summary

The catalytic dehydrogenative diboration (DHDB) of alkyne with HBpin was successfully achieved using Ir precursors under CO atmosphere, with higher selectivity in less polar solvents and higher CO pressure. the addition of a catalytic amount of tBuNC further improved the selectivity, leading to isolation of some DHDB products on the preparative scale.