Distannoxane speciation during esterification catalysis: revealing insights provided by electrospray ionization mass spectrometry.

Dimeric tetraalkyldistannoxanes are have been reported to catalyze esterification reactions, but are difficult to investigate in detail due to the lack of suitable spectroscopic handles. Electrospray ionization mass spectrometry (ESI-MS), in conjunction with a tethered charge on a tin atom, reveals that immediate decomposition to mono-tin carboxylate compounds occurs in the presence of carboxylic acid.