Copper (I) complexes with some disubstituted acetylenes and dimethylsulphoxide

Twelve copper (I) cyanide, bromide and chloride complexes with disubstituted acetylenes (RR¹C(OH)CCX; R, R¹ = CH₃ or C₂H₅, X = Br, CN or Cl) and dimethylsulphoxide (DMSO) were prepared and characterized. In all cases, the molar ratio of copper to dimethylsulphoxide and disubstituted acetylene was 4:2:1. The ¹H NMR, u.v. absorption and i.r. spectra (4000-600 cm⁻¹) of the copper (I) complexes were measured. The elemental analysis and spectral data suggest that the disubstituted acetylene is coordinated to the copper (I) atom via the π-bond using two-electron, three-centre carbon—metal bonds.