Coordination attitude of benzothiazole hydrazone in ruthenium(II) complexes: Catalytic applications on direct formation of imines via acceptorless dehydrogenative process

Abstract

New Ru(II) complexes (1–5) comprising hydrazone of the type [Ru(L1-3)(CO)(PPh3)2]Cl or [Ru(L4-5)H(CO)(PPh3)2] [L1 = (salicyl((2-(benzothiazol-2yl)hydrazono)methylphenol)) (SAL-HBT), L2 = 2-((2-(benzothiazol-2-yl)hydrazono)methyl)-6 methoxyphenol) (VAN-HBT), L3 = naphtyl-2-((2-(benzothiazol-2-yl)hydrazono)methylphenol) (NAP-HBT), L4 = 1-((benzothiazol-2-yl)-2-(furan-2-ylmethylene)hydrazine) (FUR-HBT) or L5 = 1-((benzothiazol-2-yl)-2-(thiophen-2 ylmethylene)hydrazine) (THI-HBT)] have been formulated by reacting [RuHCl(CO)(PPh3)3] with hydrazones in equal molar ratios in ethanol and chloroform medium. The formation of new complexes have been identified by spectral techniques (IR, (1H, 13C &31P) NMR), micro analyses and mass spectrometry. Single crystal XRD study was used to identify solid state structure of the compound 1 and found octahedral geometry around ruthenium metal. The dehydrogenative coupling of alcohol and amine for formation of imines have been performed using the new ruthenium(II) complexes as catalysts.