Facile synthesis of arylboronates via recyclable copper(I)-catalyzed cross-coupling of pinacolborane with aryl iodides under mild conditions

An efficient heterogeneous copper(I)-catalyzed cross-coupling of aryl iodides and pinacolborane has been developed. The reaction proceeds smoothly in THF at room temperature by using 10 mol% of MCM-41-anchored NHC-copper(I) complex [MCM-41-NHC-CuI] as catalyst and sodium hydride as base and provides a general and practical route for the synthesis of a wide variety of arylboronates in good to high yields. This heterogenized copper(I) catalyst can be facilely prepared via a simple two-step procedure starting from easily accessible and inexpensive reagents, and exhibits a higher catalytic activity than CuI and can be recycled more than ten times without any significant loss of its catalytic activity.