Reactions of cyclopalladated N-nitrosoanilines with SnIV reagents. Crystal structure of the bis cyclopalladated complex cis-Pd2

Article abstract of DOI:10.1016/0022-328X(90)85281-3

A series of cyclopalladated N-methyl-N-nitrosoanilines, >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-nitrosoanalines.The tin(IV) reagents, Me4Sn, Me3SnC<*>CPh, Buⁿ₃SnC<*>C(CH2)4CH3, Buⁿ₃SnCH=CH2, and Buⁿ₃SnCH2CH=CH2 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-Pd2, 5.The crystal structure of 5 has been determined by X-ray diffraction methods; relevant bond distances (Angstroem) and bond angles (deg.) 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.