Rigid-Rod Polymers and Model Compounds with Gold(I) Centers Bridged by Diisocyanides and Diacetylides

Binuclear alkynyl(isocyanide)gold(I) complexes have been prepared by reaction of oligomeric precursors [(AuC⋮CRC⋮CAu)n] (R = C6H4, C6H4C6H4, 2,5-C6H2Me2, CH2OC6H4C(Me)2-C6H4OCH2) with 2,6-dimethylphenyl isocyanide (XyN⋮C) to give [XyN⋮CAuC⋮CRC⋮CAuC⋮NXy] or by reaction of [(R‘C⋮CAu)n] with a diisocyanide CNRNC to give [R‘C⋮CAuCNRCAuCNC⋮CR‘] (R = C6H4, 2-MeC6H3, C6Me4, 2,5-Me2C6H2-2,5−Me2C6H2, 2,5-C6H2(t-Bu)2; R‘ = t-Bu or Ph). The products were characterized spectroscopically and, for R = 2,5-C6H2(t-Bu)2; and R‘ = Ph, by an X-ray structure determination. The molecule has a rodlike structure, and there is a bowing of the isocyanide ligand, angle CN⋮C = 168(2)°, which allows the molecules to pack in zigzag chains with short intermolecular Au··Au contacts of 3.174(1) A to give a loosely held polymeric structure. Analogous σ-bonded, conjugated rigid-rod polymeric complexes are prepared by reactions of the linear digold complexes [(AuC⋮CRC⋮CAu)n] (R = C6H4, C6H4C6H4, C6H2Me2 and CH2OC6H4C(Me)2C6H4OCH2) with app...