Process for preparing A 2-substituted benzofuran-3-yl borate ester

The invention relates to a process for preparing a stable 2-substituted benzofuran-3-yl borate ester corresponding to the formula: said process comprising contacting 3-bromo-2-substituted-benzofuran corresponding to the formula: with an C1-4 alkyllithium at a temperature less than -60° C. to form 3-lithio-2-substititued-benzofuran, contacting the 3-lithio-2-substituted- benzofuran at a temperature less than -60° C. with an borate ester corresponding to the formula: and recovering the resulting borate ester product, wherein, RW' is C1-4 alkyl; Rx is C1-10 hydrocarbyl or halohydrocarbyl; and RY independently each occurrence is C1-10 hydrocarbyl, halohydrocarbyl or trialkylsilylhydrocarbyl or 2 RY groups together are a divalent hydrocarbylene of up to 20 carbons.