Palladium-Catalyzed C(sp)-H Activation in A Monoterpene-Based Compound Under Mild Conditions: A Combined Experimental and Theoretical Mechanistic Study.

A rare example of the palladium-catalyzed sp C-H bond activation in a monoterpene-based compound has been observed in the reaction of PdCl with a (+)-3-carene-based ligand HL (HL=N-((1aS,3S,7bR)-1,1,3-trimethyl-7-phenyl-5-(pyridin-2-yl)-1a,2,3,7b-tetrahydro-1H-cyclopropa[f]quinolin-3-yl)acetamide), which yielded the [PdLCl] complex. In contrast to the vast majority of C(sp)-H activation reactions which require prolonged heating and mixing due to the inert character of the corresponding bond, the reaction reported herein proceeds rapidly under mild conditions. A theoretical insight into the ligand deprotonation has been performed by DFT calculations.