MESITYL, ALKOXY AND ARYLOXY STIBANES - 1,3-DIOXA-BENZO-2-STIBOLANES

Various mesityl, alkoxy and aryloxy-stibanes were prepared from the co rresponding mesitylchlorostibanes. The reaction of the same mesitylchl orostibanes with the 3,5-di-t-butyl catechol first leads to the format ion of a Sb V complex observed by LH NMR. Depending on the experimenta l conditions the reaction can fork from this intermediate. Intramolecu lar hydrochloride elimination when this is trapped using a tertiary am ine, leads to 2-mesityl- 1,3-dioxa-4,6-di-t-butylbenzo-2-stibolane whi le the absence of a tertiary amine allows an acidic cleavage of the me sityl-antimony bond with formation of -chloro-1,3-dioxa-4,6-di-t-butyl benzo-2-stibolane.