The unprecedented title rearrangement of 1,6-enynes has been observed with gold and platinum catalysts (see scheme, [M] = metal catalyst, Z = C(CO2Me)2, R = electron-donating group). This reaction is proposed to proceed through an open carbocationic species.
![cis-Selective single-cleavage skeletal rearrangement of 1,6-enynes reveals the multifaceted character of the intermediates in metal-catalyzed cycloisomerizations](https://www.iciq.org/wp-content/uploads/2014/03/cis-Selective-single-cleavage_AGE7892.gif)