Intermolecular Redox-Neutral Amine C-H Functionalization Induced by the Strong Boron Lewis Acid B(C6F5)3 in the Frustrated Lewis Pair Regime.

Research paper by Gerhard G Erker, Guo-Qiang GQ Chen, Gerald G Kehr, Constantin G CG Daniliuc, Markus M Bursch, Stefan S Grimme

Indexed on: 07 Feb '17Published on: 07 Feb '17Published in: Chemistry - A European Journal


N,N-Dimethylmesitylamine (5b) undergoes an intermolecular redox-neutral C-H activation/C-C coupling process upon treatment with dimethyl acetylenedicarboxylate and the strong boron Lewis acid B(C6F5)3. Similarly, the amine 5b reacts with two molar equiv. of ethyl acrylate to give the respective unsaturated coupling product with H2 transfer to the acrylic ester to form the ethyl propionate/B(C6F5)3 adduct. The amine 5b undergoes a C-H activation at the benzylic ortho sp3-carbon atom with dihydrogen formation upon treatment with Piers' borane [HB(C6F5)2]. The latter two reactions of 5b were analysed by DFT calculations.