REACTIONS OF CYCLOPALLADATED N-NITROSOANILINES WITH SN(IV) REAGENTS - CRYSTAL-STRUCTURE OF THE BIS CYCLOPALLADATED COMPLEX CIS-PD(ONN(CH3)(C6H4))2

A series of cyclopalladated N-methyl-N-nitrosoanilines, [Pd(μ-X){ONN(CH3)(C6H3Y)}]2, X = OAc, Cl, Y = 4-OCH3, 4-CH3, 4-NO2, 5-CH3, have been prepared and treated with (i) a variety of reagents to afford mononuclear palladium(II) derivatives, and (ii) R13SnR2 to yield eventually 2-R2 substituted N-methyl-N-nitrosoanilines. The tin(IV) reagents, Me4Sn, Me3SnCCPh, Bu3nSnCC(CH2)4CH3, Bu3nSnCHCH2, and Bu3nSnCH2CHCH2 all effectively transfer the R2 group to Pd, but, the mechanisms of the transfer reactions are not necessarily all the same. In some cases the presence of additional ligands, such as PPh3 or (Ph2PCH2)2, are required to suppress side reactions, especially the formation of the bis cyclopalladated complex cis-Pd{ONN(CH3)(C6H4)}2, 5. The crystal structure of 5 has been determined by X-ray diffraction methods; relevant bond distances (Å) and bond angles (°) are: Pd-N(1) = 2.082(4), Pd-N(3) = 2.078(4); Pd-C(2) = 2.005(4); Pd-C(9) = 1.997(4); N(1)-Pd-N(3) = 99.7(2), N(1)-Pd-C(9) = 168.8(2), N(1)-Pd-C(2) = 79.5(2); C(2)-Pd-C(9) = 102.4(2). It is suggested that the formation of a specific coordination sphere, involving, one cyclometallated ligand, one weakly coordinated ligand, and a monodentate carbon ligand, such as CH3, leads to production of 5. © 1990.