Picolinamide modified β-cyclodextrin/Pd (II) complex: Asupramolecular catalyst for Suzuki-Miyaura coupling of aryl, benzyl and allyl halides with arylboronic acids in water.

Highlights • A novel series of supramolecular catalysts were prepared and characterized by NMR, FT-IR, TEM, XRD, TGA, and XPS. • A picolinamide-modified β-cyclodextrin/Pd(II) complex showed very efficient catalytic activity for Suzuki-Miyaura coupling. • A proposed mechanism of the Pd(II)/Pd(IV) catalytic cycle was explored and calculated by ab initio QM/MM methods. • This hydrosoluble catalyst can be reused several times without a significant loss of activity. Abstract Novel supramolecular catalysts for Suzuki-Miyaura coupling were prepared and characterized by NMR, FT-IR, TEM, XRD, TGA, and XPS. The resulting picolinamide-modified β-cyclodextrin/Pd(II) complex (Pd(II)@PCA-β-CD) showed very efficient catalytic activity for Suzuki-Miyaura coupling of aryl, benzyl, and allyl halides with arylboronic acids in an environmentally benign aqueous solution. Various organic halides including chlorides can produce good to excellent yields with phenyl-boronic acid and a catalytic amount of Pd(II)@PCA-β-CD. This hydro-soluble catalyst was capable of being reused for at least eight runs with only a slight loss of catalytic activity. A putative mechanism of the Pd(II)/Pd(IV) catalytic cycle was also explored and calculated by ab initio QM/MM methods. [ABSTRACT FROM AUTHOR]