Mizoroki−Heck Type Reaction of Organoboron Reagents with Alkenes and Alkynes. A Pd(II)-Catalyzed Pathway with Cu(OAc)2 as an Oxidant
摘要:
[GRAPHICS]In contrast to the Pd(0)-catalyzed mechanism by Uemura, Mizoroki-Heck type reaction of boronic acids is found to proceed under a Pd(ll)mediated pathway using a catalytic amount of Pd(OAc)(2) in the presence of Cu(OAc)(2) as an oxidant. Treatment of a variety of alkenes with boronic acids, boronates, and sodium tetraphenylborate furnishes beta -arylated and alkenylated products in good to excellent yields. The reactions with norbornene, norbornadiene, and diphenylacetylene are also performed to give 1:2 or 2:1 coupling products.
Norbornene and its derivatives are diarylated or dialkenylated by aryl- or alkenyltributylstannanes, a palladium catalyst, and chloroacetone or chloroacetonitrile as a reoxidant.
[GRAPHICS]In contrast to the Pd(0)-catalyzed mechanism by Uemura, Mizoroki-Heck type reaction of boronic acids is found to proceed under a Pd(ll)mediated pathway using a catalytic amount of Pd(OAc)(2) in the presence of Cu(OAc)(2) as an oxidant. Treatment of a variety of alkenes with boronic acids, boronates, and sodium tetraphenylborate furnishes beta -arylated and alkenylated products in good to excellent yields. The reactions with norbornene, norbornadiene, and diphenylacetylene are also performed to give 1:2 or 2:1 coupling products.