Synthesis, characterization and reactivity of MoCl2(O)(O2)(OPR3)2, OPR3 = OPMePh2,OPPh3; an isomerization catalyst for some allylic alcohols

Adding one equivalent of H2O2 to compounds of stoichiometry MoCl2(O)(2)(OPR3)(2), OPR3 = OPMePh2 or OPPh3, leads to the formation of oxo-peroxo compounds MoCl2(O)(O-2)(OPR3)(2). The compound MoCl2(O)(O-2)(OPMePh2)(2) crystallized with an unequal disorder, 63%:37%, between the oxo and peroxo ligands and can be isolated in reasonable yields. MoCl2(O)(O-2)(OPPh3)(2) was not isolated in pure form, co-crystallized with MoCl2(O)(2)(OPPh3)(2) in two ratios, 18%:82% and 12%:88%, respectively, and did not contain any disorder in the arrangement of the oxo and peroxo groups. These complexes accomplish the isomerization of various allylic alcohols at rates competitive to that reported for CH3ReO3. (C) 2002 Elsevier Science B.V. All rights reserved.