Room Temperature Reduction of CO2 to Methanol by Al-Based Frustrated Lewis Pairs and Ammonia Borane

AlX3 (X = Cl or Br) and PMes(3) (Mes = 2,4,6-C6H2Me3) react to form weak Lewis adducts but also react with CO2 to give Mes(3)P(CO2)(AlX3)(2) (X = Cl; Br). These species react rapidly with excess ammonia borane at room temperature to give CH3OH upon quenching with water.