Synthesis and characterization of O, O-alkylene dithiophosphate derivatives of dimethyl-and trimethylgermane. Crystal structure of

Abstract

The O, O-alkylene dithiophosphate derivatives of dimethyl- and trimethylgermane [Formula: see text], [Formula: see text], [Formula: see text],[Formula: see text], [Formula: see text], and Me3Ge[S2POCH2CEt2CH2O] have been prepared in 70–85% yields by reaction of the salts of the appropriate O,O-alkylene dithiophosphoric acid with dichlorodimethyl-and chlorotrimethylgermane. The compounds were characterized by infrared, Raman, and 1H, 13C, and 31P NMR spectroscopy. The crystal structure of [Formula: see text], was determined and it crystallizes as monoclinic in the space group P21/a (No. 14) with the cell parameters a = 12.368(6) Å, b = 6.897(2) Å, c = 17.923(3) Å, β = 99.00(3)°, V = 2450(2) Å3, Z = 4, R = 0.0455, and Rw = 0.0394. The environment about germanium is essentially that of a distorted tetrahedron resulting in a S—Ge—S angle of 89.9(1)° and a C—Ge—C angle of 121.6(5)°. In contrast with analogous non-cyclic diorganodithiophosphatogermanes, the terminal sulfur atoms are oriented towards germanium rather than away from it to give an average [Formula: see text] intramolecular distance of 3.49(3) Å. The spectra are interpreted as indicating that the dithiophosphate groups are linked in identical fashion in all compounds 1–6. The 1H and 13C NMR spectra are of particular interest in that, unlike the spectra reported previously for related species, the substituents on the atoms in both the five- and six-membered rings maintain their non-equivalence in solution.