New organotin(IV) derivatives containing the anionic dihydrobis(1-imidazolyl)borate [H2B(im)2]- have been synthesized from the reaction between SnRnX4-n (R = Me, Ph, nBu or Cy; n = 1-3) acceptors and [K{H2B(im)2}·(DMAC)] (DMAC = dimethylacetamide). Mono-nuclear complexes of the type {[H2B(im)2]RnSnCl4-n-1} have been obtained, which have been fully characterized by elemental analyses and FT-IR in the solid state and by NMR (1H and 119Sn) spectroscopy, conductivity measurements and electrospray ionization mass spectrometry (ESIMS) in solution. ESIMS spectra of a methanol solution of the complexes show the existence of hydrolysed species for mono- and di-organotin(IV) derivatives, while non-hydrolysed aggregates are detected for triorganotin(IV) derivatives