ACID-CATALYZED ATTACK OF THE DINITROGEN LIGAND IN THE CIS-(ME(2)PHP)(4)MO(N-2)(2) AND TRANS-(PH(2)PCH(2)CH(2)PPH(2))(2)W(N-2)(2) COMPLEXES BY NITRONIUM AND NITROSONIUM CATIONS WITH THE FORMATION OF NITROGEN-OXIDES

The interaction of labeled dinitrogen complexes cis-(Me(2)PhP)(4)Mo(N- 15(2))(2) and trans(dPPe)(2)W(N-15(2))(2) With non-labeled nitronium a nd nitrosonium fluoroborates, (NO2BF4)-N-14 and (NOBF4)-N-14, in sulfo lane at room temperature in the presence of H2SO4 results in rapid for mation of labeled nitrous and nitric oxides ((NNO)-N-15-N-14, (NO)-N-1 5), as well as (NN)-N-15-N-14. The yield of the products depends on th e reagent ratio and reaches 10-20 mel. % per mole of a complex under o ptimum conditions. The mechanism of the reactions found is proposed. I t involves the step of protonation of the dinitrogen ligand to form th e corresponding hydrazido(2-) derivatives, which are then attacked by nitronium or nitrosonium cations. In accordance with the mechanism pro posed, it was established that the hydrazido(2-) complexes, (Me(2)PhP) (3)Mo((N2H2)-N-15)Cl-2 and (dppe)(2)W((N2H2)-N-15)Cl-2, are capable of forming (NNO)-N-15-N-14, (NO)-N-15, and (NN)-N-15-N-14 under the acti on of (NO2BF4)-N-14 and (NOBF4)-N-14 in the absence of an acid.