The behavior of the K&02C18-NOCI, Moz(C,H3-02)4-NOCl, and [(CzH5).,N] &o&,-NOCI systems in ethyl acetate has been investigated. In every case, only products were found in which the molybdenummolybdenum multiple bonds of the starting complexes had been cleaved, After appropriate work-up of the K&02C18-NOCl system immediately after reaction, the complexes K2Mo(NO)C15 and Mo(NO)C13*2(C,H5)$'0 were isolated. infrared evidence indicated that these compounds were contaminated with species containing molybdenumoxygen bonds, and indeed, extended reaction times resulted in marked decreases in the relative intensity of the absorption characteristic of the N-O stretch and increases in the intensities of those absorptions attributable to molybdenum-oxygen linkages. Reaction of NOCl with Mo~(C~H~O~)~ gave, after treatment of the ethyl acetate solution with triphenylphosphine oxide, practically quantitative yields of Mo(NO)C13~2(C6H5)Jp0. Again, the compound was apparently contaminated with substances having molybdenum-oxygen bonds. It is worth noting that the initial reactions of NOCl with KJ!ozCls and Mo~(C~H~O~)~ occurred with little oxidation of the dipositive molybdenum. The major products obtained after work-up of the [(C2H5)JV]Mo2C19-NOCl system were ](GH&Nl zMo(NO)Cl,, ](CZHSWI~ MoC14(H20), (x = l-2), and Mo02Cl,*2(CeH5)Q0. It is proposed that [(CzH5)Jt] 2Mo(NO)C15 is formed by reaction of a molybdenum(IH) species with NO, the latter arising from the reduction of NOCl.