SYNTHESIS, X-RAY CRYSTAL-STRUCTURES, AND NMR-SPECTROSCOPY OF [PPH(4)]2[M(TE4)2], M=HG, CD, ZN

The compounds [PPh(4)](2)[M(Te-4)(2)], M = Hg, Cd, Zn, have been prepa red by reactions in DMF of appropriate metal salts with polytelluride solutions. X-ray crystal structure determinations were performed on si ngle crystals of each compound. Crystal data for [PPh(4)](2)[Hg(Te-4)( 2)]: tetragonal, P $($) over bar$$ 4, a = 21.365(3) Angstrom, c = 11.2 68(2) Angstrom, V = 5143 Angstrom(3), R = 0.079. Crystal data for [PPh (4)](2)[Cd(Te-4)(2)]: tetragonal, I $($) over bar$$ 4, a = 21.442(3) A ngstrom, c = 11.259(2) Angstrom, V = 5176 Angstrom(3), R = 0.045. Crys tal data for [PPh(4)](2)[Zn(Te-4)(2)]: tetragonal, I $($) over bar$$ 4 , n = 21.396(4) Angstrom, c = 11.169(2) Angstrom, V = 5113 Angstrom(3) , R = 0.094. These crystal structures are surprisingly complex, and th e anions exhibit disorder; nevertheless. the anions have the expected structure of metal atoms coordinated tetrahedrally by two Te-4(2-) che lates. Te-125 NMR spectra of these compounds and of [PPh(4)](2)[Pd(Te- 4)(2)] are reported, and assignments of metal-bound and ring-bound Te nuclei are given. The resulting trends in the Te-125 chemical shifts p arallel those noted previously for the Se-77 chemical shifts in the se lenometalate analogues.