Organotin halides and their hydrolysed species studied in solution by positive and negative ion electrospray mass spectrometry

Abstract

Hydrolysis products of the organotin compounds R 3SnCl (R = Ph, Me or Bu n), Ph 3SnBr and Ph 2SnCl 2 have been investigated by electrospray mass spectrometry. Both positive and negative ion modes were employed to obtain information on the range of charged species produced in aqueous acetonitrile solution. The positive ion electrospray spectra of the triorganotin species yielded aggregates [(R 3Sn) n (OH) n-1 ] +, alongside R 3Sn + and solvated cations, including [R 3Sn(NCCH 3) +]. Addition of pyridine (py) to hydrolysed Ph 3SnCl afforded predominantly [Ph 3Sn(py)] +. In the negative ion spectra a number of species could be identified. Solutions of Ph 3SnX (X = Cl or Br) yielded [Ph 3SnX 2] −, [Ph 3SnX(OH)] −, [Ph 3SnO] − and [Ph 3SnOSnPh 3X] −, whilst those of Ph 2SnCl 2 showed chiefly [Ph 2SnCl 3] −. Me 3SnCl yielded [Me 3SnCl 2] − accompanied by [Me 3SnOSnMe 3(OH)] −, whereas Bu 3 nSnCl gave [Bu 3 nSnCl 2] − and [Bu 3 nSnCl(OH)] −. Addition of Cl −, Br − and I − to a hydrolysed solution of Bu 3 nSnCl allows identification of all six mixed dihalostannate complexes [Bu 3 nSnXY] − (X, Y = Cl, Br or I).