Novel synthesis of (hetero)biaryls: when multicomponent reactions meet hyperbaric activation

In continuation of our studies on metal-free hyperbaric activation of alkynes in Diels-Alder reactions,2 we envisaged the possibility of developing a multicomponent protocol to generate in situ a suitable diene via acid-catalyzed enolacetylation of the corresponding (hetero)arylideneacetone with isopropenyl acetate. This intermediate then undergoes high-pressure promoted Diels-Alder reaction in the presence of an electron-poor dienophile (i. e. methyl propiolate) to give the resultant cycloadduct. Interestingly, the reaction is completely regioselective and the cycloadducts can be easily oxidized to the corresponding (hetero)biaryls