Synthesis of an oxygen-linked germinal frustrated Lewis pair and its application in small molecule activation.

Reaction of Mes 2 P(O)Li with (C 6 F 5 ) 2 BCl gave access to an oxygen-linked germinal intramolecular frustrated Lewis pair Mes 2 P(O)B(C 6 F 5 ) 2 (1). Compound 1 is stable at room temperature and only decomposes when heated to 90 °C. NMR analysis and theoretical analysis revealed the frustrated nature between the boron and phosphorus centers. Compound 1 shows typical frustrated Lewis pair reactivity when treated with dihydrogen, carbon dioxide, alkyne and alkene. The reaction of 1 with isoprene resulted in selective formation of 3,4-phosphoryl/boryl addition product 8.