Saphan O. Akiri, S. O. Ojwach
Apr 15, 2021
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0
Influential Citations
7
Citations
Journal
Journal of Organometallic Chemistry
Abstract
Abstract 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.