Approach to Di/Triorganotin(IV) Cations via Hydrolysis of Stannate Salts Bearing Alkanesulfonate Ligands.

An in-depth study of the class of organotin cations bearing weakly coordinating trifluoromethanesulfonate/arylsulfonate has led to key insights into their stability, structural aspects, and role as catalysts. Related chemistry with alkanesulfonate ligands remains a missing link due to the strong Sn-O bond. The study reported herein describes the scope of diorganostannates, [ n -Bu 4 N][R 2 Sn(OSO 2 R 1 ) 3 ] (R = n -Bu, R 1 = Me( 1 ), Et( 2 ); R = Ph, R 1 = Me( 3 )), as reactive substrates in the presence of adventitious water to afford [ n -Bu 2 SnOH(OSO 2 Me)] ( 4 ), [ n -Bu 2 Sn(H 2 O) 4 ][ n -Bu 4 N][OSO 2 Et] 3 ·H 2 O ( 5 ), and [Ph 2 Sn(H 2 O) 4 ][ n -Bu 4 N] 2 [OSO 2 Me] 4 ( 6 ), respectively, the latter two being the first examples of salt cocrystals comprising tetra(aqua)diorganotin cations. Hydrolysis of 3 in the presence of 1,4-bis((1H-imidazol-1-yl)methyl)benzene (bix) as the N-donor ligand proceeds via disproportionation and yields [Ph 3 Sn(bix)](OSO 2 Me) ( 7 ) along with an insoluble solid, likely derived from the hydrolysis of PhSn(OSO 2 Me) 3 . Direct evidence of this phenomenon can be gleaned from ESI-MS of 3 , which identifies mass clusters corresponding to [Ph 3 Sn(OSO 2 Me) 2 ] - and [PhSn(OSO 2 Me) 3 -H + ] - . X-ray crystallographic studies of 1 - 7 are reported to establish their structural identity and the role of alkanesulfonate anions in the formation of supramolecular assemblies.