Coordination assembly enables highly selective catalytic hydroaminomethylation of olefins. Issue 4 (12th December 2022) - Qian, Chun
Abstract : The l / b selectivity in hydroaminomethylation of olefins could be boosted to 99 : 1 with 98% yield by using recyclable self-supported NHC–Rh(i ) catalysts. Abstract : Hydroaminomethylation (HAM) of olefins constitutes one of the most promising and practical methods to produce amines, but control of the selectivity between linear and branched products is still challenging. Herein, a series of solid main-chain NHC–rhodium(i ) polymers prepared by coordination assembly were found to be highly efficient single-site catalysts in the HAM of olefins. A dramatic enhancement of both productivity (up to 98% yield) and linear selectivity (up to 99 : 1) was observed, largely due to the constraints imposed by the extended coordination assembly structure of the solid catalysts. As well as the broad substrate scope, a record turnover number of 2.1 × 10 5 was achieved, and the solid catalyst could be reused more than 18 times without obvious loss of activity and selectivity. The protocol has a high tolerance of sensitive functional groups, and its utility was exemplified by the synthesis of several leading pharmaceuticals directly from allyl alcohols or heterocyclic amines without any protection or deprotection operations, and at a scale of up to one gram.