The oxochlorovanadates PPh4[VOCl3OH], PPh4[VOCl4], (PPh4)(2)[VOCl4]center dot 2CH(3)CN, and (PPh4)(2)[VOCl4]center dot 4CH(3)CN with remarkable deviations from the square-pyramidal anion structure

Starting from vanadium which was not free of oxide, VCl4 was prepared; its reaction with PPh4Cl in the presence of K2S5 in dichloromethane yielded PPh 4[VOCl3OH]. From V2S5, PPh4Cl and S2Cl2 in acetonitrile, sulfur crystallize d first, then PPh4[VOCl4], and then (PPh4)(2)[VOCl4]. 4CH(3)CN. Upon standi ng with the mother liquor at -18 degrees C, the latter was converted to (PP h4)(2)[VOCl4]. 2CH(3)CN. According to its X-ray crystal structure determina tion, PPh4[VOCl3OH] (space group Pbca, a = 1105.5, b = 1920.8, c = 2242.8 p m, Z = 8) has nearly square-pyramidal anions that are associated to chains by O-H ... Cl bridges. PPh4[VOCl4] is isotypic with AsPh4[VOCl4] and has st rictly square-pyramidal anions (space group P4/n, a = 1254.0, c = 765.0 pm, Z = 2). In (PPh4)(2)[VOCl4]. 4CH(3)CN (space group P (1) over bar, a = 128 1.3, b = 1276.6, c = 1841.5 pm, alpha = 84.11 degrees, beta = 83.96, gamma = 64.31 degrees, Z = 2) the square pyramid of the VOCl42- ion is distorted towards a trigonal-bipyramidal shape (C-2v symmetry) having trans-ClVCl ang les of 145.88 degrees and 156.87 degrees and O=V-Cl angles of 107 degrees a nd 101.6 degrees. In (PPh4)(2)[VOCl4]. 2CH(3)CN (space group P (1) over bar a = 1017.1, b = 1029.3, c = 2416.0, alpha = 77.74 degrees, beta = 79.99 de grees, gamma = 78.94 degrees, Z = 2), the VOCl42- structure is even closer to trigonal-bipyramidal, with trans-ClVCl angles of 133.25 degrees and 165. 80 degrees and O=V-Cl angles of 113.3 degrees and 97 degrees.