Reaction of n-butyltin dihydroxy chloride with carboxylic and phosphinic acids: Crystal structures of the ladder [{Sn(n-Bu)(O < inf > 2 < /inf > CCHPh < inf > 2 < /inf > )} < inf > 3 < /inf > Cl < inf > 2 < /inf > O < inf > 2 < /inf > ] < inf > 2 < /inf > and the unsolvated cluster [{Sn(n-Bu)(O < inf > 2 < /inf > PPh < inf > 2 < /inf > )Cl < inf > 2 < /inf > }{Sn(n-Bu)(O < inf > 2 < /inf > PPh < inf > 2 < /inf > ) < inf > 2 < /inf > (OH)}] < inf > 2 < /inf >

Abstract

The reaction of n-butyltin dihydroxy chloride Sn(n-Bu)(OH)2Cl (1) with carboxylic and phosphorus based acids has been investigated. Treatment of 1 with diphenylacetic acid affords the ladder [{Sn(n-Bu)(O2CCHPh2)}3Cl2O 2]2 (2), which upon treatment with AgO2CMe or triethylamine/water, leads to the prismane [{Sn(n-Bu)(O)(O2CCHPh2)]6 (3). Compound 1 reacts with dicyclooctyl phosphinic acid to afford the mixed nuclear cluster [{Sn(n-Bu)(OH)(O2P(C8H15)2)} 3O]+[{Sn(n-Bu)Cl2(O2P(C 8H15)2)}2(OH)]- (4). From the reaction of 1 with half or one mole equivalent each of t-BuP(O)(OH)2 and Ph2POOH in toluene, the unsolvated extended cluster [{Sn(n-Bu)(O2PPh2)Cl2}{Sn(n-Bu)(O 2PPh2)2(OH)}]2 (6) is directly isolated, suggesting the preferential formation of this skeleton. Compound 6 upon hydrolysis in the presence of triethylamine gives the known O-capped cluster, [{Sn(n-Bu)(OH)(O2PPh2}3O]+ [O2PPh2]- (7). Whereas 2 has a hexanuclear Sn6O4 skeleton with three different tins, 6 has an extended tetranuclear [Sn2(OH)]2 stannoxane framework. The major structural difference between 2 and other known ladder structures is the presence of a five coordinated terminal tin in 2. Comparison of the stannoxane skeleton in 2 and 6 with other known tin cages is also described.