Scope and Limitations of the PdCl₂(MeCN)₂/Fe(OTf)₃-Cocatalyzed Aerobic Olefin Aminoboration

Herein, we report the Pd(II)/Fe(III)-cocatalyzed aerobic aminoboration of norbornene with nitrogen nucleophiles and B₂pin₂, employing 10 mol % Fe(OTf)₃ cocatalyst. These conditions are limited to strained cyclic olefins; α-olefins fail to produce appreciable yields under the reaction conditions. The reaction scope is demonstrated for the aminoboration of norbornene with an array of nitrogen nucleophiles (27 examples with up to 98% isolated yield), including imides, sulfonamides, and amides. Moreover, mechanistic investigations demonstrate that Fe(OTf)₃ promotes rapid transmetalation with B₂pin₂; with activated strained cyclic alkenes, this increases the rate of aminoboration. Conversely, with less active α-olefins, the oxidative degradation of B₂pin₂ is faster than aminoboration.