Synthesis, structure and solution NMR properties of (Ph4P)[M(SeC[O]Tol)3], M = Zn, Cd and Hg

Metal selenocarboxylate salts (PPh4)[M(SeC[O]Tol)3] (M = Zn (1), Cd (2) and Hg (3); Tol = C6H4-p-CH3) have been synthesized by reacting Zn(NO3)2 .6H2O, Cd(NO3)2 .4H2O or HgCl2 with (Na+)TolC[O]Se- and PPh4Cl in the ratio of 1 : 4 : 1. The structures of these compounds were determined by single-crystal X-ray diffraction methods. The crystal structures contain discrete cations and anions. In the each anion, the metal center is bound to three TolC[O]Se ligands, primarily through Se, though some long M...O interactions also occur. NMR spectra (113Cd, 199Hg and 77Se, as appropriate) are reported for solutions of [M(SeC[O]Tol)3]-, and of [M(SeC[O]Tol)3](-) - [M(SC[O]Ph)3]- mixtures (M = Zn-Hg), in CH2Cl2 at reduced temperatures. In addition, ESI-MS data have been obtained for [M(SeC[O]Tol)(3)](-) - [M(SC[O]Ph)3]- mixtures (M = Zn-Hg) in acetone and in CH2Cl2. The NMR and ESI-MS studies show that the complexes [M(SeC[O]Tol)n(SC[O]Ph)(3-n)]- (n= 3-0) persist in solution.