Preparation of Acetylide Complexes

Ethynide and ethynediide complexes with M —C bonds may be prepared according to methods which were already described as well as by reactions of acetylene with transition metal salts  

These reactions take place in water, alcohols, and other polar solvents. The type of the compound formed depends on the transition metal and the acidity of the solution. From ammonia solutions of Ag(I) and Cu(I) salts, acetylides possessing the composition M2C2 are precipitated, while Ag2S04 and CU2SO4 in sulfuric acid solution afford soluble ethynides  

Acetylides are also prepared by direct reaction of metals, their oxides and hydrides with carbon at high temperatures (1800-2300 K) or by reaction of metals with hydrocarbon vapors. The latter method is utilized for preparation of acetylides of scandium, yttrium, and the lanthanides. 

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