In situ synthesis of dimeric distannoxane compounds using diorganotin bis(carboxylate) in basic solution

Twelve diorganotin bis(carboxylate) R2Sn(O2CR')2 were synthesized using alkyl tin oxide (methyl, n-butyl, and n-octyl), and benzoic acid derivatives with para substituents (NH2, H, Cl, and NO2). Comprehensive characterization through infrared (IR), mass spectrometry (MS), nuclear magnetic resonance (NMR), elemental analysis (EA), and X-ray diffraction confirmed their structures. The diorganotin bis(carboxylate) compounds were placed in situ in an NMR tube under basic conditions with deuterated chloroform as a solvent, forming dimeric distannoxane compounds ([R2Sn(O2CR')]2O)2. Various bases, such as piperidine, piperazine, aniline, pyridine, sodium hydroxide, and tetrabutyl ammonium hydroxide, were employed. The integration of NMR, MS, and X-ray data provides crucial evidence for the formation of dimeric distannoxanes and their possible reaction mechanism under basic conditions.