937241-17-3Relevant articles and documents
Phosphine ligands in the Palladium-catalysed methoxycarbonylation of ethene: Insights into the catalytic cycle through an HP NMR spectroscopic Study
De La Fuente, Veronica,Waugh, Mark,Eastham, Graham R.,Iggo, Jonathan A.,Castillon, Sergio,Claver, Carmen
, p. 6919 - 6932 (2010)
Novel cis-1,2-bis(di-tertbutyl-phosphinomethyl) carbocyclic ligands 6-9 have been prepared and the corresponding palladium complexes [Pd(O 3SCH3)(L-L)][O3SCH3] (L-L = diphosphine) 32-35 synthesised and characterised by NMR spectroscopy and Xray diffraction. These diphosphine ligands give very active catalysts for the palladium-catalysed methoxycarbonylation of ethene. The activity varies with the size of the carbocyclic backbone, ligands 7 and 9, containing four- and six-membered ring backbones giving more active systems. The acid used as co-catalyst has a strong influence on the activity, with excess trifluoroacetic acid affording the highest conversion, whereas excess methyl sulfonic acid inhibits the catalytic system. An in oper-ando NMR spectroscopic mechanistic study has established the catalytic cycle and resting state of the catalyst under operating reaction conditions. Although the catalysis follows the hydride pathway, the resting state is shown to be the hydride precursor complex [Pd(O3SCH3)(L-L)][O3SCH3], which demonstrates that an isolable/detectable hydride complex is not a prerequisite for this mechanism.
CARBONYLATION OF ETHYLENICALLY UNSATURATED COMPOUNDS
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Paragraph 0203, (2016/10/09)
PROBLEM TO BE SOLVED: To provide a process for the carbonylation of ethylenically unsaturated compounds including vinyl esters and a process for the production of 3-hydroxypropanoate esters or 3-hydroxypropanoic acids. SOLUTION: The process comprises reacting the compound with carbon monoxide in the presence of a source of hydroxyl groups and of a catalyst system. The catalyst system is obtainable by combining: (a) a metal of Group 8, 9 or 10 or a compound thereof: and (b) a bidentate ligand of general formula (I): X1(X2)-Q2-A-R-B-Q1-X3(X4). COPYRIGHT: (C)2015,JPOandINPIT