222017-54-1Relevant articles and documents
Steric and electronic factors in the promoting activity of diphosphine ligands in cyclohexene hydrocarbomethoxylation catalyzed by palladium acetate
Nifant'ev,Batashev,Toloraya,Tavtorkin,Sevost'yanova,Vorob'ev,Bagrov,Aver'yanov
, p. 462 - 469 (2012)
Cyclohexene hydrocarbomethoxylation catalyzed by Pd(OAc) 2-p-Toluenesulfonic acid-diphos-phine systems has been investigated for a wide range of diphosphine structures and concentrations. The fac-Tors controlling the activity of the palladium-containing catalysts include the hydrocarbon moiety of the ligand and the mutual arrangement of the phosphine groups. A comparison between the promoting effects of monophosphine and diphosphine ligands has demonstrated that bridged trans-diphosphines are more effi-cient in kinetic and concentration terms (TOF and P/Pd ratio, respectively). In particular, the promoting activity of diphosphines is one order of magnitude higher than that of triphenylphosphine, and this effect is attained at 8-65 times lower P/Pd ratios. It is discussed how the catalytic properties of the systems depend on the chelate effect and on the geometric compatibility between the diphosphine structure and the arrange-ment of vacant s and d orbitals of the palladium center. Pleiades Publishing, Ltd., 2012.
Process for the preparation of aldehydes
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, (2008/06/13)
Process for the preparation of aldehydes by hydroformylation of an alkenically unsaturated compound in the presence of (a) Pd, a Pd compound, Pt and/or a Pt compound, (b) an anion of a carboxylic acid with a pKa 1 R2 -M-R-M-R3 R4, wherein M is P, As or Sb, R is a divalent organic bridging group having at least 3 carbon atoms in the bridge, and R1, R2, R3 and R4 are hydrocarbon groups.
Process for the carbonylation of ethylenically unsaturated compounds
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, (2008/06/13)
Process for the preparation of a carboxylic ester or acid by reacting an ethylenically unsaturated compound in which each of the carbon atoms of the carbon-carbon double bond is secondary or tertiary, with CO in the presence of an alkanol or water, respectively, and of a catalytic system prepared by combining:-, a) Pd and/or a Pd compound, b) a strong acid, except hydrohalogenic and carboxylic acids, and c) a bidentate ligand, using a molar ratio of acid to ligand of greater than 0.5.