Nitriles hydrolysis of to amides

S (2)-hydroxy-3-butenenitrile from acrolein and HCN trans hydrocyanation using, for instance, acetone cyanohydrin Hydrolysis of nitriles to amides, e.g. acrylonitrile to acrylamide Isomerization of glucose to fructose Esterifications and transesterifications Interesterify positions 1 and 3 of natural glycerides Oxidation of glucose to gluconic acid, glycolic acid to glyoxalic acid... 

Bacterial enzymes have been reported to catalyze the hydrolysis of nitriles [118][121], A nitrilase (EC 3.5.5.1) acts to hydrolyze aromatic nitriles directly to the carboxylic acid. A nitrile hydratase (a lyase, EC 4.2. E84) acts on short-chain aliphatic nitriles to form the amide. As discussed below, the hydrolysis of nitriles to amides is also documented in mammals, but little appears known about the enzymes involved. 

An interesting method for the hydrolysis of nitriles to amides involves two redox processes with H2O2 and a peroxycarboximidic acid (236) intermediate stage, as shown in equation 84. The mechanism of hydrolysis was established for acetonitrile and benzonitrile... 

Reaction LXXXIX. Hydrolysis of Nitriles to Amides. (B., 18, 355.)— When nitriles are heated with acids or alkalis they are hydrolysed to the corresponding acids passing intermediately through the amides. It is possible only in a few instances (e.g., oxamide) to stop the hydrolysis at this intermediate stage, unless alkaline hydrogen peroxide is employed, when the amide is obtained in almost theoretical yield. Both methods of hydrolysis are illustrated in the following preparations. 

The hydrolysis of nitriles to amides is applicable to C-cyanoglycosides. As shown in Scheme 2.2.19, BeMiller, et al.,14 utilized titanium tetrachloride in acetic acid to effect the conversion of a peracetylated C-cyanogalactoside to its corresponding primary amide. This transformation was effected in an 80% yield. Furthermore, base hydrolysis of the nitrile provides a clean conversion to the carboxylic acid.15 Thus through the methods already mentioned, extensions with standard organic techniques allow the formation of a wide variety of useful functional groups. 

The hydrolysis of benzylphenylamine [15, 16] was investigated in a batch autoclave at 385 °C in the pressure range of 22 to 100 MPa, and was found to lead to the formation of aniline, benzyl alcohol and toluene as the main products. The selectivity towards hydrolysis is increased at higher pressure and in the presence of NaCl. The hydrolysis of nitriles to amides and further to alcohols has been investigated mainly at subcritical conditions in batch reactors (Scheme 14.1). 

Hydrolysis of nitriles to amides. Nitriles form complexes with palladium chloride. When heated with water, these complexes are partially hydrolyzed to amides with liberation of PdCl2 The hydrolysis can also be carried out in situ without isolation of the complex. Yields of amides are low in the case of CH3C=N or C6HsC=N (20-30%) yields are in the range of 70-85% in the case of XCHjC N. 

Functional models of nitrile hydratase should reproduce the key reactions occuring at the active site. In addition to the catalytic hydrolysis of nitriles to amides, these also include photo-induced cleavage of coordinated nitric oxide and thiolate oxygenation under aerobic conditions. The nitrosyl complex 3 displays significant structural and electronic features in common with NHasCdark These spectroscopic similarities, however, do not translate to a functional model of photo-regulated NO dissociation. 

Hydrolysis of nitriles to amides (Table 2.2) in the presence of visible light in a weakly basic medium has been earried out to examine the catalytic activity of the MnOa nanorods synthesized on the anionic resin surface. " From the literature it is confirmed that the hydrolysis of nitriles to amides requires strongly acidic or alkaline conditions and sometimes may be quite drastic. In 1966, during oxidation of alcohols. 

The microbial hydrolysis of nitriles to amides or carboxylic acids often does not proceed with high enantioselectivity, but it offers a valuable and mild alternative method to the harsh reaction conditions usually required for this conversion using traditional methodology. As a consequence, it has proven to be a very useful and competitive method in the chemoselective transformation of nitriles on an industrial scale. 

Lactonization Isomerization Oxidation of alcohols to aldehydes ketones Reduction of aldehydes and ketones to alcohols Oxidation of amino groups to nitro groups Hydrolysis of nitriles to amides and caibo Q lic acids Functional group alteration... 

Acetamides have been prepared in moderate to good yield from alcohols by reaction with acetonitrile and sulphuryl chloride. It has been found that the hydrolysis of nitriles to amides can be effected in excellent yield using potassium hydroxide in t-butanol if the amide produced is relatively insoluble in water. Experimental details for the large scale anodic oxidation of iV-formyl derivatives of amines to a-methoxyalkylamides have been recorded, and an interesting synthesis of trichloroacetamides from allylic alcohols via a thermal [Att + 2a] rearrangement has been described (Scheme 50). ... 

Partial hydrolysis of nitriles to amides is carried out with an acid or with an alkaline solution of hydrogen peroxide if the formed amide has properties suitable for identification. The reaction conditions (temperature, concentration, and duration of hydrolysis) differ in different cases, and the reaction is usually carried out in 95% H2SO4 at 25 — 80 °C. 

Homogeneous catalysts based on Pt(ll) complexes have also been successful in the hydrolysis of nitriles to amides. The early report on this topic appeared about 30 years ago [136, 137]. However, the first reactive and selective catalyst, reported in 1986 by Togler and Jensen [138], was [PtH(PMe3)2(H20)][0H], a species that catalyzes the hydrolysis of acetonitrile to acetamide at rates of 178 mol/(mol of catalyst h), at 80°C and gives as many as 6000 turnovers. 

However, the most recent and useful applications of Pt catalysis to the hydrolysis of nitriles to amide were achieved with homogeneous platinum phosphinito catalysts [139, 140], The catalyst precursors are coordination compounds of Pt(ll) with secondary phosphine oxides and the results obtained with [PtH(PMe20H) (PMc2-0)2H] with aUcyl, alkenyl, and aryl nitriles are reported in Scheme 76. 

---