Trimethyl borate, reaction with Grignard reagents

Trimethyl borate, reaction with Grignard reagents, 49, 91... 

The synthesis of alkyl-, aryl-, and 1-alkenylboronic acids or their esters from Grignard or lithium reagents and trialkylborates is a classical and efficient method for making relatively simple boron compounds in large quantities (Scheme 2-6) [25]. The stereocontrolled synthesis of alkenylboronic acids and esters involves the reaction of a (Z)- or ( )-2-buten-2-ylmagnesium bromide with trimethyl borate [26]. 

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