Dinuclear antimony(V) complexes with diethylphosphinate bridges

The binuclear antimony(V) complexes Cl3Sb(O)[(C2H5)(2)PO2](2)SbCl3 Cl3Sb(O) [(C2H5)(2)PO2](OCH3)SbCl3, (2) and Cl3Sb(O)[(C2H5)(2)PO2](OH)SbCl3 (3) are prepared by reaction of diethylphosphinic acid with antimony(V) chloride, w ater and methanol in different molar ratios, The yields are optimized contr olling the progress of the reactions by the P-31-NMR signals. The crystal a nd molecular structures of 1 to 3 are determined by X-ray analysis. I and 3 crystallizes monoclinic in the space groups P2(1)/m and P2(1)/c reap. and 2 crystallizes in the orthorhombic space group Pnma. As shown by the NMR sp ectra in solution 3 undergoes a rapid intermolecular hydrogen exchange.