KOORDINATIONSCHEMIE FUNKTIONELLER PHOSPHORYLIDE. VI. KOMPLEXCHEMISCHE, IR- UND NMR-SPEKTROSKOPISCHE UNTERSUCHUNGEN AN 2-CYAN-2-TRIPHENYLPHOSPHORANYLIDEN-DITHIOESSIGSAEURE UND IHREN ALKYLESTERN

Article abstract of DOI:10.1016/0022-328X(83)85026-8

The IR and NMR (1H< 31P, 13C) spectra of 2-cyano-2-triphenylphosphoranylidene dithioacetic acid and some alkyl esters are described.Besides ν(CN) at 2160-2190 cm^-1, an intense IR absorption band between 1300 and 1340 cm^-1 with a high ν(CS) share is observed for all α-cyanodithiocarboxylic derivatives.The 13C NMR spectra show a large shielding of δ(C(1), phenyl) like in arylphosphonium cations and a high 1J(PC) value for the ylide carbon signal which is shifted downfield ca. 65 ppm compared to cyanomethylenephosphorane.By treatment of the α-cyanodithioacetic acid (LH) or the lithium salt (LLi) with carbonylmetal halides, the chelate complexes cis-(CO)4MnL, fac-(CO)3(PPh3)MnL and 2 are obtained.The alkyl esters (LR) are weak neutral ligands which form monocoordinated pentacarbonyl complexes. (CO)5W(LR), with irradiated W(CO)6.The coordination site of the ligand is discussed on the basis of the IR and 13C NMR spectra.