Photolytic reactions of binuclear thiooxalate complexes - Crystal and molecular structure of hydrogensulfidopyridinebis(triphenylphosphane)copper(I)

Article abstract of DOI:10.1002/zaac.19976230121

Solutions of the binuclear, thiooxalato bridged complexes with capping triphenylphosphane ligands are lightsensitive and decompose mainly with decomposition of the bridging thiooxalate. From μ-1,1-Dithiooxalato-bis[bis(triphenylphosphane)copper(I)], [{(Ph₃P)₂Cu}₂(i-dto)], in dichloromethane the binuclear copper(I) complex μ-dichlorotris(triphenylphosphane)dicopper(I), [(Ph₃P)₂CuCl₂Cu(Ph₃P)], with the total lost of the bridging thiooxalato ligand is formed. μ-Trithiooxalato-bis-[bis(triphenylphosphane)copper(I)], [{(Ph₃P)₂Cu}₂(trto)], decomposes in pyridine with the formation of hydrogensulfidopyridinebis(triphenylphosphane)copper(I), [(Ph₃P)₂(py)CuSH]. This complex crystallizes in the triclinic space group P 1, with the unit cell parameters a = 9,488(2) A, b = 10,472(3) A, c = 19,351(3) A, α = 85,03(2)°, β = 86,99(2)° and γ = 68,36(2)°. Contrastingly, the bridging thiooxalate ligand in the corresponding binuclear tetrathiooxalate complex, [{(Ph₃P)₂Cu}₂(tto)], obviously remains unchanged. The proposed reaction pathways are supported by the results of Extended Hueckel Calculations.