Brønsted Acid Catalyzed PhSe Transfer versus Radical Aryl Transfer: Linear Codimerization of Styrenes and Internal Olefins

Brønsted acid p-TsOH·H2O-catalyzed hydrovinylation of styrenes with internal olefins α-oxo ketene dithioacetals was efficiently achieved in the presence of N-phenylselenophthalimide (N-PSP), regioselectively affording Markovnikov phenylselenative hydrovinylation products through PhSe transfer of the phenylseleno ketene dithioacetal intermediates. Radical reduction of the resultant PhSe-alkyl-substituted ketene dithioacetals with AIBN/n-Bu3SnH gave the corresponding anti-Markovnikov hydrovinylation products formally from the linear codimerization of styrenes and the internal olefins.