REDOX REACTIONS BETWEEN MOLYBDENUM OR TUNGSTEN HEXAFLUORIDES AND P-BLOCK, F-BLOCK OR D-BLOCK ELEMENTS IN ACETONITRILE - COMPARISONS WITH REACTIONS INVOLVING NITROSONIUM FLUOROMETALLATES, THE EFFECT OF FLUORIDELIGAND TRANSFER AND REDOX INHIBITION DUE TO SURFACE OXIDE

The outcome of reactions between antimony, bismuth, lanthanum, neodymi um, europium, thulium, gold or nickel and the one-electron oxidizing a gents, molybdenum hexa-fluoride, tungsten hexa-fluoride or the nitroso nium cation in the presence of acetonitrile, cannot always be predicte d on the basis of the relative oxidizing abilities of the reagents. Fl uoride ligand transfer from hexafluorometallate(V) anions to the solva ted cation is a major factor in reactions that involve oxidation of an timony and bismuth, although the solvated bismuth(III) cation can be s tabilized by the macrocycle, 1,4,8,11-tetraazacyclotetradecane. Passiv ation of the metal surface by an oxide layer appears to be important i n lanthanum and nickel oxidations, resulting in an apparent inversion of reactivity between molybdenum and tungsten hexafluorides. (C) 1998 Elsevier Science S.A. All rights reserved.