Gold(I)/Gold(III) Catalysis Merging Oxidative Addition and π-Alkene Activation.

The hetero-arylation of alkenes with aryl iodides has been efficiently achieved with the (MeDalphos)AuCl complex via Au(I)/Au(III) catalysis. The possibility to combine oxidative addition of aryl iodides and π-activation of alkenes at gold is demonstrated for the first time. The reaction is robust and general (>30 examples including internal alkenes, 5, 6 and 7-membered rings). It is regioselective and leads exclusively to trans addition products. The (P,N) gold complex is most efficient with electron-rich aryl substrates, which are troublesome with alternative photoredox / oxidative approaches. In addition, it actuates a very unusual switch in regioselectivity from 5-exo to 6-endo cyclization between the Z and E isomers of internal alkenols.