PREPARATION AND CHARACTERIZATION OF A SERIES OF BROMODIPHENYL(N,N-DIALKYLDITHIOCARBAMATO)TELLURIUM(IV) COMPOUNDS WHERE R = ME, ET, ISO-PR, BU, AND OF CHLORODIPHENYL(N,N-DIBUTYLDITHIOCARBAMATO)TELLURIUM(IV) AND DIPHENYLBIS(N,N-DIBUTYLDITHIOCARBAMATO)TELLURIUM(IV) - CRYSTAL-STRUCTURE OF PH2TEBR[S2CNET2] AND PH2TE[S2CNBU2]2

The series Ph2TeBr[S2CNR2], where R = Bu, Pr, i-Pr, Et, and Me, as well as Ph2TeCl[S2CNR2] and Ph2Te[S2CNR2]2, where R = Bu, Pr, have been synthesized and characterized by elemental analysis and vibrational spectroscopy. Comparisons of the effect of changing R groups and halogen atoms can be made based on the two crystal structures determined herein along with earlier work. The geometry about tellurium is consistent with that of a distorted sawhorse structure where the dithiocarbamate groups are monodentate (or anisobidentate). The crystal structures of Ph2TeBr[S2CNEt2], 4, and Ph2Te[S2CNBu2]2, 7, were completed. The cell parameters for 4 are a = 11.204(3) angstrom, b = 14.106(11) angstrom, c = 13.867(10) angstrom, alpha = 99.62(6)-degrees, beta = 102.76(5)-degrees, gamma = 87.73(4)-degrees, V = 2107 angstrom3, Z = 4, R = 0.0448, and R(w) = 0.0489 and for 7 are a = 19.392(6) angstrom, b = 9.622(2) angstrom, c = 19.089(6) angstrom, beta = 104.70(2)-degrees, V = 3445(2) angstrom3, Z = 4, R = 0.0397, and R(w) = 0.0439. Nuclear magnetic resonance spectra are not simple and indicate that several species are present in solution, as rearrangements and reductive elimination take place.