This idea relates to the synthesis of salts of dodecahydrododecaborate B12H12 (2-). In the proposed process a metal hydride is reacted with an alkyl borate in the presence of a Lewis base to produce Lewis base-borane compex, which is thermally decomposed to produce salts of B12H12 (2-), while alkyl borare is recovered from the reaction by-product and is recycled.