Synthesis and infrared and H-1,C-13, Sn-119 NMR spectra of some tris- and bis(1-butyl)tin(IV) naphthoates and hydroxynaphthoates

The synthesis and structure of tris(1-butyl)tin(IV) and bis(1-butyl)tin(IV) 1-naphthoates, 2-naphthoates, 1-hydroxy-2-naphthoates, 2-hydroxy-1-naphthoates, 3-hydroxy-2-naphthoates as well as the groups of the corresponding tetrakis(1-butyl)dinaphthoato- and tetrakis(1-butyl)bis(hydroxynaphthoato)distannoxanes have been studied in solutions of both coordinating and noncoordinating solvents by means of infrared and multinuclear (H-1, C-13 and Sn-119) NMR spectroscopies. In the solutions of noncoordinating solvents, all the tris(1-butyl)tin(IV) compounds are present as isolated monomeric molecules with pseudotetrahedral environment of the central tin atom, or as strongly deformed cis-trigonally bipyramidal chelate complexes with anisobidentate carboxylic group. The bis(1-butyl)tin(IV) compounds form molecular pseudooctahedral complexes with chelate anisobidentate carboxylic groups of naphthoate or hydroxynaphthoate ligands. The (1-butyl)chlorotin(IV) compounds are molecular complexes containing a chelate-bound carboxylic group, their tin atom having a pentacoordinated environment of the bond partners, The tetrakis(1-butyl)dinaphthoato- and tetraskis(1-butyl)bis(hydroxynaphthoato)distannoxanes form dimeric molecular complexes with two pentacoordinated tin atoms and two hexacoordinated ones. In solutions of a coordinating solvent (hexadeuteriodimethyl sulfoxide), the tris(1-butyl)tin(IV) compounds form trans-trigonally bipyramidal complexes with one molecule of the solvent, whereas the bis(1-butyl)tin(IV) and bis(1-butyl)chlorotin(IV) compounds form trapezoidally bipyramidal complexes with two molecules of the solvent. The dimeric tetrakis(1-butyl)bis(hydroxynaphthoato)distannoxanes are monomerized by coordinating solvent, each monomeric unit adding two solvent molecules per one tin atom. The environment of the tin atom is then pseudooctahedral. The hydroxyl groups of naphthoate systems do not take part in any bonds to the tin atom in any of the compounds studied.