Palladium-Catalyzed Oxidative Annulation of 1-Hydroxy-o-Carborane withInternal Alkynes:Facile Synthesis of Carborane-Fused Oxaborolest

of main observation and conclusion A palladium catalyzed oxidative annulation of 1-hydroxy-o-carborane with internal alkynes via regioselective B(3)—H bond activation has been developed for facile synthesis of a series of QB-substituted carborane-fused oxaboroles.These molecules can undergo intramolecular oxidative dehydrogenative coupling to afford carborane-fused large n systems for potential applications in organic materials.The reaction mechanism is also proposed,involving hydroxy deprotonation,nucleopalladation of alkyne,regioselective electrophilic B—H substitution and reductive eiiimination.