Cu(I) Coordination Polymers as the Green Heterogeneous Catalysts for Direct C-H Bonds Activation of Arylalkanes to Ketones in Water with Spatial Confinement Effect.

To develop coordination polymers (CPs) as catalysts to selectively catalyze the reaction of C-H bond activation of arylalkanes to their homologous ketones, three new Cu(I)-based coordination polymers (CuI-CPs) [CuI(aas-TPB)]n (1), [CuBr(ass-TPB)CH3CN]n (2), and {[Cu(ass-TPB)]Cl}n (3) (TPB = N,N,N-tris(3-pyridinyl)-1,3,5-benzenetricarboxamide) were synthesized. Structural variations from a herringbone fashion one-dimensional framework of 1 to a two-dimensional framework of 2 containing a 48-membered macrocycle and a cationic three-dimensional framework of 3 filled with Cl- anions were observed arising from the different halogen ions (I-, Br-, and Cl-). 1-3 were used as the green heterogeneous catalysts to catalyze direct C-H bond activation reactions of arylalkanes to ketones under mild reaction conditions with water as solvent. Handy product separation, convenient reaction procedures, and recyclability of these catalysts make the catalytic system fascinating. Moreover, the CuI-CPs performed the reaction with high regioselectivity due to the unique spatial confinement effect of CPs.