Suzuki Miyaura cross-coupling of 2-chloropyrazine with arylboronic acids catalyzed by novel palladium(II) ONO pincer complexes

[Display omitted] •The four new palladium(II) complexes were synthesized.•The single-crystal study revealed that the synthesized complexes were in distorted square planar geometry.•Creation of C-C bond was successfully attained by C-Cl bond activation via the Pd(II) complexes as homogeneous catalysts.•The capability of the complexes as homogeneous catalysts are good and exhibits superior activity under low catalyst loading.•The catalyst was recyclable up to five consecutive runs. The four novel ONO pincer type hydrazone ligands (H2L1, H2L2, H2L3 and H2L4) and their corresponding palladium(II) complexes of the type [Pd(L)(PPh3)] were synthesized and characterized by using FT-IR, UV–visible, 1H, and 13C NMR and spectroscopic techniques. And single-crystal XRD data revealed that all these complexes were adopted a distorted-square planar structure. These Pd (II) complexes were employed as catalysts for the Suzuki-Miyaura cross-coupling reactions of 2-chloropyrazine with various arylboronic acids and found superior activity under the optimized conditions in H2O/toluene media. The catalytic reaction progressed well with a low catalyst loading (0.01%) under an open-flask condition. The catalyst has demonstrated excellent recyclability.