Nitriles palladium hydration

Several cationic palladium(II) aqua complexes, [Pd(H20)4], cis-[PdL(H20)2] (L = en, methionine methyl ester, l,5-dithiacycloocta-3-ol), and [Pd(dien)(H20)], serve as the active catalyst for the selective hydration of various nitriles to the corresponding carboxamides, e.g., CHCI2CN was hydrated to CHCl2C(0)NH2 in the presence of... 

Kostic et al. reported the use of various palladium(II) aqua complexes as catalysts for the hydration and alcoholysis of nitriles,435,456 decomposition of urea to carbon dioxide and ammonia, and alcoholysis of urea to ammonia and various carbamate esters.457 Labile aqua or other solvent ligands can be displaced by a substrate. In many cases, the coordinated substrate thus becomes activated toward nucleophilic addition of water or alcohols. 

Kostic et al. recently reported the use of various palladium(II) aqua complexes as catalysts for the hydration of nitriles.456 crossrefil. 34 Reactivity of coordination These complexes, some of which are shown in Figure 36, also catalyze hydrolytic cleavage of peptides, decomposition of urea to carbon dioxide and ammonia, and alcoholysis of urea to ammonia and various carbamate esters.420-424, 427,429,456,457 Qggj-jy palladium(II) aqua complexes are versatile catalysts for hydrolytic reactions. Their catalytic properties arise from the presence of labile water or other solvent ligands which can be displaced by a substrate. In many cases the coordinated substrate becomes activated toward nucleophilic additions of water/hydroxide or alcohols. New palladium(II) complexes cis-[Pd(dtod)Cl2] and c - Pd(dtod)(sol)2]2+ contain the bidentate ligand 3,6-dithiaoctane-l,8-diol (dtod) and unidentate ligands, chloride anions, or the solvent (sol) molecules. The latter complex is an efficient catalyst for the hydration and methanolysis of nitriles, reactions shown in Equation (3) 435... 

Catalytic hydrogenation of iV-(o-nitrophenyl)aminoacetonitriles 192 with palladium(ll) oxide hydrate gives high yields of quinoxaline A -oxides 193 through condensing the reduced hydroxylamine intermediate with nitrile (Equation 31) <2001EJ0987>. 

Nitriles can be catalytically hydrated, principally by palladium complexes (equation 185). In an initial study, [Rh(OH)(CO)(PPh3)2] (140) was found to be the best catalyst.642 Other complexes exhibiting catalytic activity were the iridium analogue of complex (140), [Pt(CsHa)(diphos)] (141) and [Pt(C6H8)(PPh3)2] (142). 

An efficient palladium-catalyzed protocol for the hydration of alkyl and aryl nitriles to amides has been disclosed, employing acetaldoxime as efficient water delivering surrogate to nitrile. A plausible mechanism was suggested involving Pd(ll)-catalyzed nitrile-oxime coupling followed by disruption of the intermediate into benzamide and acetonitrile in a concerted manner [81-83] (Scheme 39). 

Ishizuka A, Nakazaki Y, Oshiki T (2009) The hydration of nitriles catalyzed by the combination of palladium nanoparticles and copper compounds. Chem Lett 38 360-361... 

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