24987-68-6Relevant academic research and scientific papers
Structural studies and applications of water soluble (phenoxy)imine palladium(II) complexes as catalysts in biphasic methoxycarbonylation of 1-hexene
Akiri, Saphan O.,Ojwach, Stephen O.
, (2021)
Reactions of the ligands; sodium 4?hydroxy-3-((phenylimino)methyl)benzenesulfonate (L1), sodium 3-(((2,6-dimethylphenyl)imino)methyl)-4-hydroxybenzenesulfonate (L2) and sodium 3-(2,6-diisopropylphenyl)imino)methyl)-4-hydroxybenzenesulfonate (L3) with Pd(OAc)2 afforded the respective palladium(II) complexes [Pd(L1)2] (PdL1), [Pd(L2)2] (PdL2) and [Pd(L3)2] (PdL3). In addition, treatment of the non-water soluble ligands 2-((phenylimino)methyl)phenol (L4), 2-(((2,6-dimethylphenyl)imino)methyl)phenol (L5) and 2-((2,6-diisopropylphenyl)imino)methyl)phenol (L6) with Pd(OAc)2 gave the corresponding complexes [Pd(L4)2] (PdL4), [Pd(L5)2] (PdL5) and [Pd(L6)2] (PdL6) in good yields. Solid state structures of complexes PdL1 and PdL4 established the formation of bis(chelated) square planar neutral compounds. All the complexes formed active catalysts in the methoxycarbonylation of 1-hexene, affording yields of up to 92% within 20 h and regioselectivity of 73% in favour of linear esters. The catalytic activity and selectivity of the complexes depended on the steric encumbrance around the coordination centre. The water soluble complexes displayed comparable catalytic behaviour to the non-water soluble systems. The complexes could be recycled five times with minimal changes in both the catalytic activities and regio-selectivity.
Pd(II) catalyzed transformation of Schiff bases in complexes of the type trans-[PdCl2(NH2Ar-X)2] (X = H, CH3, Cl): Reactivity with aldehydes and Heck coupling reaction
Kumari, Niraj,Yadav, Vinod Kumar,Zalis, Stanislav,Mishra, Lallan
, p. 554 - 563 (2012/06/30)
Schiff bases of type (R-Ph-N=CH-Ph-CH=N-Ph-R), where, R = H (L 1), CH3 (L2) and Cl (L3), in presence of cis-[Pd(en)Cl2] or [Pd(DMSO)2Cl2] (en = 1,2-diaminoethane, DMSO = dimethylsulphoxide) give trans-[PdCl 2(NH2Ph)2] (1), trans-[PdCl2(NH 2PhCH3)2] (2) and trans-[PdCl 2(NH2PhCl)2] (3). The complexes are characterized using spectroscopic (IR, UV-vis and NMR) and X-diffraction techniques. The H-bonding interaction generates multinuclear supramolecular structure in complex (2) and (3). Complex (1) on reaction with benzaldehyde, salicylaldehyde and 4-carboxybenzaldehyde yields complexes of the type [PdCl2(PhN=CHPh)2] (4), [Pd(PhN=CHPhO)2] (5) and [PdCl2(PhN=CHPhCOOH)2] (6) respectively. The structures have been optimized using density functional theory at B3LYP level. Heck coupling reactions of bromobenzene with acrylonitrile and bromobenzene with ethyl acrylate in the presence of complexes (1), (2) and (3) have been carried out separately.
