The mechanism of acid-catalyzed nucleophilic substitution in decahydro-closo-decaborate(2-) anions

The reactions of salts formed by the B10H102- anion with carboxylic acids were studied. From the model systems Cat(2)B(10)H(10) + HCOOH (Cat = Et4N+, Bu4N+, Ph4P+, Ph4As+), several intermediates were isolated and characterized. A mechanism was proposed for the replacement of the exo-polyhedral hydrogen atoms in B10H10 by carboxylate groups in the reactions of Cat(2)B(10)H(10) with carboxylic acids.