2-(PHENYLTELLUROMETHYL)TETRAHYDROFURAN (L-1) AND 2-(2-(4-METHOXYPHENYL)TELLUROETHYL)-1,3-DIOXOLANE (L-2) AND THEIR PALLADIUM(II) AND PLATINUM(II) COMPLEXES

The nucleophile [ArTe-] generated ill situ borohydride solution of Ar2 Te2, reacts with 2-(chloromethyl) tetrahydrofuran and 2-(2-bromoethyl) -1,3-dioxolane resulting in L-1 and L-2, respectively. The complexes o f palladium(II) and platinum(II) with L-1/L-2 having stoichiometries [ MCl2 . L-2], [ML2](ClO4)(2), [(DPPE)ML2](ClO4)(2), [(PPh3)(2)ML2](ClO4 )(2) and [(phen)ML2](ClO4)(2) (where L = L-1/L-2 DPPE = Ph2PCH2CH2PPh2 , phen = 1,10-phenanthroline and M = Pd/Pt) have been synthesized. IR, H-1, Te-125{H-1} and P-31{H-1} NMR and UV-vis spectral data of these species in conjunction with their molar conductance and molecular weig ht data have been used to authenticate the new species. In all complex es (1-20) the ligands L-1 and L? are coordinated through tellurium and in the complexes of formula [ML2](ClO4)(2) (M = Pd, Pt) the ligand is bidentate with the oxygen atom used in complexation. In solution, com plexes PtCl2L2 exist as a mixture of cis and trans isomers whereas onl y the trans isomer was observed for the palladium analogues. The [(phe n)PdL2](ClO4)(2)(Q) quenches O-1(2) readily. The plot of log [Q] vs ti me is linear. Mechanism compatible with the experimental observations is proposed. (C) 1997 Elsevier Science Ltd.