2-Hydroxy-2-phenylacetonitrile

It should be evident that the maximum yield of a particular enantiomer normally available from a racemic mixture is 50%. However, in some enzymic catalysed kinetic resolutions it is possible to obtain >50% yield of one enantiomer from a racemate. For this to occur, it is necessary to have the desired chemical reaction, e.g. enzyme-catalysed stereoselective esterification, occurring at the same time as the enantiomers of the racemic starting compound are interconverting under equilibrium conditions. A successful example of this technique is provided by ben-zaldehyde cyanhydrin (2-hydroxy-2-phenylacetonitrile), whose R and S enantiomers, 49 and 50, respectively, equilibrate in the presence of a basic anion-exchange resin (Scheme 3.5). In the presence of lipase, (S)-ben-zaldehyde cyanhydrin acetate 51 was formed in 95% yield and in 84% enantiomeric excess (see Inagaki et al.u and Ward15). 

C14H15NO7 309.275 Obt. by hydrol. of Amygdalin (see 2-Hydroxy-2-phenylacetonitrile) and oxidn. of the resulting L-Mandelonitrile-p-glucoside. Claimed to be an anticancer agent, but there is no rigorous scientific evidence for this. Mp 214-216°. 

Girgensohnia spp. G. diptera Bge. contains N-methylpiperidine and dipterine, CHH14N2, m.p. 87-8°, [a]D 0° hydrochloride, m.p. 177-8°, picrate, m.p. 189-190°, and picrolonate, m.p. 242-3°, which was later shown to be N-methyltryptamine.i G. oppositiflora Pall, contains N-methylpiperidine and girgensonine, C13H13ON2, m.p. 147-8°, [aJjj 0°. The latter forms a hydrochloride, m.p. 145-8°, and a picrolonate, m.p. 192-4°, and on hydrolysis by alkali yields piperidine, hydrocyanic acid and p-hydroxybenzaldehyde, indicating that it is N-piperidyl-p-hydroxy-phenylacetonitrile, and this has been confirmed by comparison with a synthetic specimen. ( (1) Juraschevski and Stepanova, J. Gen. Chem. Russ., 1939, 9, 2203 Juraschevski, ibid., 1940, 10, 1781. (2) Juraschevski and Stepanova, ibid., 1946, 16, 141). 

OH - Obtained by reaction of p-hydroxy-phenylacetonitrile with 2-methoxyhy-droquinone (Hoesch reaction) [5293,5351]. 

Phenylacetonitrile reacts with diethyl sulfite to give 3-hydroxy-4,5-diphenylisothia2ole, together with other products (75SST(3)541). Phenylketene reacts with compound (199) to give a mixture of the isothiazolidinone (200) and the pyrrole (201 Scheme 33) (77SST(4)339, 79SST(5)345). 

The recombinantly expressed nitrilase from Pseudomonas fluorescens EBC 191 (PFNLase) was applied in a study aimed at understanding the selectivity for amide versus acid formation from a series of substituted 2-phenylacetonitriles, including a-methyl, a-chloro, a-hydroxy and a-acetoxy derivatives. Amide formation increased when the a-substituent was electron deficient and was also affected by chirality of the a- stereogenic center for example, 2-chloro-2-phenylacetonitrile afforded 89% amide while mandelonitrile afforded 11% amide from the (R)-enantiomer but 55% amide was formed from the (5)-enantiomer. Relative amounts of amide and carboxylic acid was also subject to pH and temperature effects [87,88]. 

Schwartz, M. A. Zoda, M. Vishnuvajjala, B. Mami, I. A convenient synthesis of o- andp-hydroxy substituted phenylacetonitriles and phenethylamines./. Org. Chem. 1976, 43, 2502-2503. 

Treatment of diphenylacetonitrile in toluene with sodium amide and 2-chloro-pyrazine gave 2-(C-cyano-C,C-diphenylmethyl)pyrazine (1021), and 2-vinylpyrazine with phenylacetonitrile and sodium heated at 120-130° for 10 minutes gave 2-(3 -cyano-3 -phenylpropyl)pyrazine (731). 2-Amino-5-bromomethyl-3-cyano-pyrazine with sodium hydride and methyl cyanoacetate in tetrahydrofuran formed the dialkylated product (56) (1031). 2-Amino-3-mercapto-5,6-dimethylpyrazine in methanol with potassium hydroxide and chloroacetonitrile gave 2-amino-3-cyanomethyIthio-5,6-dimethylpyrazine (1229), and 2-carboxypyrazine refluxed with chloroacetonitrile and triethylamine in ethyl acetate for 45 minutes gave the cyanomethyl ester (1317). 2-Hydroxy 5-methyl-3-propylpyrazine with cyanogen halides in aqueous sodium hydroxide-dimethylformamide at 0-5° gave l-cyano-5-methyl-2-oxo-3-propyl-l, 2-dihydropyrazine (1123). 

Hydroxy-4-benzyloxy-l-(2-amino-alhyl)-benzol5 11 g 3-Hydroxy-4-benzyloxy-phenylacetonitril werden in 40ml Methanol und 40m/ fliissigem Ammoniak mit 5 g Raney-Kobalt bei 120 bar und 85-90° 5 Stdn. hydriert. Man filtriert vom Katalysator ab, dampft i. Vak. ein und lost den Riickstand in 200 ml lauwarmer 3 n Salzsaure. Man filtriert erneut, dampft i. Vak. ein und kristallisiert den Riickstand aus Athanol/Ather um Ausbeute (//>-drochlorid) 10,8 g (83% d.Th.) F 197-199°. 

Cyanopyrazine reacts with cyclopropyllithium to give pyrazinyl cyclopropyl ketone <91JHC1147>. Benzoyl pyrazine is formed by oxidative decyanation of a-pyrazinyl-a-phenylacetonitrile under phase-transfer catalytic conditions <87JHC1061 >. (2-Hydroxy-2-phenylethyl)pyrazines undergo retro-ene reaction on pyrolysis to yield methylpyrazines and benzaldehyde quantitatively <87JOC397i>. 

Phenyl-1-acetyl-2-ethyl)-3-hydroxy-4-coumarin 3-(1 -Phenyl-2 -acetylethyl)-4-hydroxycoumarin 3-(a-Phenyl-p-acetylethyl)-4-hydroxycoumarin. See Warfarin Phenyl acetyl nitrile. See Phenylacetonitrile Phenyl acid phosphate CAS 701-64-4... 

Obtained by reaction of phenylacetonitrile with 2,6-di-hydroxy-4-methoxytoluene (Hoe-sch reaction) (52%) [5353]. 

Preparation by hydrolysis of 4-hydroxy-3-(l -oxopropyl) phenylacetonitrile with dilute sulfuric acid in boiling acetic acid for 2 h (82%) [6942]. 

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