206358-12-5Relevant articles and documents
Highly stereoselective hydrocyanation of optically pure α- sulfinylaldehydes
Cifuentes Garcia, Marta M.,Garcia Ruano, Jose Luis,Martin Castro, Ana M.,Rodriguez Ramos, Jesus H.,Fernandez, Inmaculada
, p. 859 - 864 (1998)
Diastereoselective hydrocyanation of enantiomerically pure 2-p-tolyl- sulfinylacetaldehyde and 2-p-tolylsulfinylpropanal with Et2AlCN catalyzed by ZnBr2 is described. The sulfur configuration controls the stereochemical course of the reaction. Hydrolysis of the resulting cyanohydrins and further desulfurization yielded the corresponding α-hydroxyamides in high ees (90%).
Bis(allyl)-ruthenium(IV) complexes with phosphinous acid ligands as catalysts for nitrile hydration reactions
Tomás-Mendivil, Eder,Francos, Javier,González-Fernández, Rebeca,González-Liste, Pedro J.,Borge, Javier,Cadierno, Victorio
, p. 13590 - 13603 (2016/09/04)
Several mononuclear ruthenium(iv) complexes with phosphinous acid ligands [RuCl2(η3:η3-C10H16)(PR2OH)] have been synthesized (78-86% yield) by treatment of the dimeric precursor [{RuCl(μ-Cl)(η3:η3-C10H16)}2] (C10H16 = 2,7-dimethylocta-2,6-diene-1,8-diyl) with 2 equivalents of different aromatic, heteroaromatic and aliphatic secondary phosphine oxides R2P(O)H. The compounds [RuCl2(η3:η3-C10H16)(PR2OH)] could also be prepared, in similar yields, by hydrolysis of the P-Cl bond in the corresponding chlorophosphine-Ru(iv) derivatives [RuCl2(η3:η3-C10H16)(PR2Cl)]. In addition to NMR and IR data, the X-ray crystal structures of representative examples are discussed. Moreover, the catalytic behaviour of complexes [RuCl2(η3:η3-C10H16)(PR2OH)] has been investigated for the selective hydration of organonitriles in water. The best results were achieved with the complex [RuCl2(η3:η3-C10H16)(PMe2OH)], which proved to be active under mild conditions (60 °C), with low metal loadings (1 mol%), and showing good functional group tolerance.
Synthesis of aliphatic (S)-α-hydroxycarboxylic amides using a one-pot bienzymatic cascade of immobilised oxynitrilase and nitrile hydratase
Van Pelt, Sander,Van Rantwijk, Fred,Sheldon, Roger A.
experimental part, p. 397 - 404 (2009/12/01)
A one-pot bienzymatic cascade combining a hydroxynitrile lyase (Manihot esculenta, E.C. 4.1.2.10) and a nitrile hydratase (Nitriliruptor alkaliphilus, E.C. 4.2.1.84) for the synthesis of enantiopure aliphatic α- hydroxycarboxylic amides from aldehydes is described. Both enzymes were immobilised as cross-linked enzyme aggregates (CLEAs). Stability tests show that the nitrile hydratase CLEAs are sensitive to water-immiscible organic solvents as well as to aldehydes and hydrogen cyanide (HCN), but are remarkably stable and show useful activity in acidic aqueous environments of pH 4-5. The cascade reactions are consequently carried out by using a portionwise feed of HCN and moderate concentrations of aldehyde in acidic aqueous buffer to suppress the uncatalysed hydrocyanation background reaction. After optimisation, this method was used to synthesise five different kinds of aliphatic α- hydroxycarboxylic amides from the corresponding aldehydes with good yields and with enantiomeric purities comparable to those obtained for the α-hydroxynitriles in the microaqueous hydrocyanation using hydroxynitrile lyase and an excess of HCN.