From dicopper diacetylide (Cu-C≡C-C≡C-Cu) to carbyne

Hydrolysis of dicopper diacetylide Cu-C≡C-C≡C-Cu in HCl solution yields diacetylene as major product together with a mixture of polyynes and minor amounts of carbonaceous matter. After I month ageing the main hydrolysis product from dicopper diacetylide is insoluble carbonaceous matter (23.47% by weight) together with diacetylene and its superior homologues (polyynes formed from solid state oxidative coupling reaction) which have been qualitatively and quantitatively identified by electronic spectroscopy. Similar behaviour and results are observed on dicoppper acetylide Cu-C≡C-Cu. In the carbonaceous insoluble matter recovered after hydrolysis, the presence of carbyne was detected by FT-IR spectroscopy.

Dicopper acetylide Cu-C≡C-C≡C-Cu and dicopper acetylide, irrespective for the degree of oxidation reached in air, undergo a controlled thermal decomposition by heating under reduced pressure yielding in few seconds carbyne and copper(I) oxide, both identified by FT-IR spectroscopy.