External oxidant-free cross-coupling of arylcopper and alkynylcopper reagents leading to arylalkyneElectronic supplementary information (ESI) available: 1H NMR and 13C NMR spectra for all compounds. See DOI: 10.1039/c7ra03348f

External oxidant-free oxidative cross-coupling between arylcopper and alkynylcopper has been performed, which provides a new way for the formation of arylalkyne with high selectivity. External oxidant-free cross-coupling of arylcopper and alkynylcopper reagents for the formation of arylalkynes was performed.