PREPARATION AND X-RAY STRUCTURE DETERMINATION OF PENTA-OXOMOLYBDENUM(IV) AND TETRACYANO-OXOMOLYBDENUM(IV) ANIONS - THE INFLUENCE OF WATER ON THEIR REACTIVITY

Several penta- and tetracyanooxomolybdenum(IV) anions have been synthesized containing different numbers of H2O molecules, either coordinated or present as crystallisation molecules. The influence of these molecules on the reactivity of the complex, especially towards O2, is discussed. Three compounds were characterized by x-ray structure determination. [Mo(O)(CN)5(H2O)2-(MeCN)2][PPH4]4Cl belongs to triclinic space group P-1 with a = 13.146(3)-angstrom, b = 16.944(5)-angstrom, c = 21.761(6)-angstrom, alpha = 84.72(2)-degrees, beta = 87.15(2)-degrees and gamma = 85.25(2)-degrees. The volume of the unit cell is 4678(6)-angstrom-3 with z = 2. The structure was refined to R = 6.5%. [Mo(O)(CN)4(H2O).6H2O][PPh4]2. belongs to monoclinic space group P2(1)/n with a = 15.313(2)-angstrom, b = 19.983(3)-angstrom, c = 17.006(2)-angstrom, beta = 100.51(2)-degrees. The volume of the unit cell is 5117(3) angstrom-3 with z = 4. The structure was refined to R = 8.7%. [Mo(O)(CN)4(MeCN)](PH3)2N]2 belongs to triclinic space group P-1 with a = 13.770(4)-angstrom, b = 16.292(5)-angstrom, c = 16.889(5)-angstrom, alpha = 73.23(2)-degrees, beta = 72.02(2)-degrees and gamma = 71.57(2)-degrees. The volume of the unit cell is 3342(3)-angstrom-3 with z = 2. The structure was refined to R = 7.2%.