Diverse Reactivity of Dialkylaluminum Dimesitylboryloxides [(μ-Mes2BO)AlR2]2. Synthetic and Structural Study
journal contributionposted on 17.11.2000, 00:00 by Romana Anulewicz-Ostrowska, Sergiusz Luliński, Janusz Serwatowski, Kinga Suwińska
Several stable dimeric dialkylaluminum boryloxides of the formula [(μ-Mes2BO)AlR2]2 (R = Me (1), Et (2), iBu) have been prepared from dimesitylborinic acid Mes2BOH and trialkylaluminums R3Al. Compound 1 has been characterized by X-ray diffraction. These compounds exhibit diverse reactivity toward protonolytic reagents depending on the bulkiness of these reagents. Treatment of 1 with tert-butyl alcohol afforded crystalline species trans-[(μ-tBuO)(Mes2BO)AlMe]2 (3), which is the first example of a mixed system containing boryloxide and alkoxide ligands together. Most surprisingly, Mes2BOH was found to undergo catalytic decomposition in the presence of [(μ-Mes2BO)AlR2]2 via the unexpected cleavage of one boron−carbon bond. The molecular structure of the decomposition product, i.e., trimesitylboroxin [MesBO]3 (4) is reported.