TE-125 NUCLEAR-MAGNETIC-RESONANCE STUDY AND X-RAY CRYSTAL-STRUCTURES OF ORGANOTELLURONIUM SALTS

The proton-noise-decoupled tellurium-125 NMR spectra of a series of organotelluronium salts R2Te+R'X- are reported, including the precursors of nonstabilized, semistabilized, and stabilized telluronium ylides (R = n-Bu, i-Bu, Me, and Ph; R' = CnH2n+1 (n = 1-6), Ph, CH2CH=CH2, CH2C=CSiMe3, CH2CH=CHSiMe3, CH2CH=CHC02Et, CH2CO2CH3, CH2CO2C2H5, CH2CONHBu-i, CH2CON(CH2)3CH2, CH2CON(CH2)4CH2, and CH2CN; X = Cl, Br, I, and BPh4). The Te-125 NMR chemical shifts are measured in CDCl3, DMSO-d6, or solution relative to neat Me2Te and range from 418 ppm for (CH3)3Te+ I- to 675 ppm for (C6H5)2Te+CH3-BPh4. The coupling constants of Te-C and Te-H of several telluronium salts are also reported. Furthermore, X-ray crystals structures of (CH3)2Te+CH3 I- (14), i-Bu2Te+C6H5 Br- (4), and (C6H5)2Te+CH3-BPh4 (23) are reported. Compound 14 belongs to the monoclinic system, space group P2(1)/n, with Z = 4, a = 7.123(2) angstrom, b = 9.675(3) angstrom, c = 11.334(3) angstrom, and beta = 107.71(3)-degrees. Compound 4 crystallizes also in the monoclinic system, space group P2(1)/c, with Z = 4, a = 9.161(4) angstrom, b = 14.496(8) angstrom, c = 13.198(6) angstrom, and beta = 106.86(3)-degrees. Compound 23 belongs to an orthorhombic system, space group P2(1)2(1)2(1), with Z = 4, a = 8.777(5) angstrom, b = 16.689(5) angstrom, and c = 20.523(8) angstrom.Chemistry, Inorganic & NuclearChemistry, OrganicSCI(E)14ARTICLE51575-15811