Reductive Opening of Oxetanes Catalyzed by Frustrated Lewis Pairs: Unexpected Aryl Migration via Neighboring Group Participation.

B(C 6 F 5 ) 3 was found to catalyze an unusual double reduction of oxetanes by hydrosilane with aryl migration via neighboring group participation. Control experiments suggested that the phenonium ion serves as the key intermediate. Minor modification of this protocol also led to simple hydrosilylative opening of oxetanes.