Frustrated Lewis Pair Mediated Csp3 -H Activation

Abstract

The cleavage of a Csp³ -H bond by an N/B frustrated Lewis pair (FLP) is reported. Upon mild heating, the ambiphilic molecule (2-NMe₂ -C₆ H₄ )₂ BH activates the C-H bond of a methyl group in α position of a nitrogen atom to generate an unprecedented N-B heterocycle. Upon further heating, the novel species rearranges through a hydride abstraction/1,2-aryl shift sequence. The mechanistic details of these transformations are investigated by quantum mechanical calculations.

Keywords: Csp3−H activation; N-B heterocycles; amineboranes; frustrated Lewis pairs; quantum mechanical calculations.