Benzonitrile, reactions

Il ichev YV, Kuhnle W, Zachariasse KA (1998) Intramolecular charge transfer in dual fluorescent 4-(dialkylamino) benzonitriles. Reaction efficiency enhancement by increasing the size of the amino and benzonitrile subunits by alkyl substituents. J Phys Chem A 102(28) 5670-5680... 

Benzo crown ether, 39 115-116 Benzoin, catalytic oxidation scheme, 33 62 Benzonitrile, reaction with hexafluoroacetone, 30 268... 

Irradiation of a mixture of furan and benzene gives mainly the [4 + 4] cycloadduct 242 a substantial amount of the adduct 243 derived by addition of carbons 2 and 5 of furan and 1 and 3 of benzene is also obtained. Both phenylace-tylene and benzonitrile undergo regio- and stereospecific 2,6,2,5-photocycloaddition to furan, illustrated in Scheme 105 for the benzonitrile reaction, to give the [4 + 3] cycloadducts. 

Zanella AW, Ford PC (1975) Base hydrolisis of coordinated benzonitriles. Reactions of rhodium (III) and iridium(III) complexes, hiorg Chem 14 700-701... 

Now add the diazonium solution to the potassium cupro-cyanide in small quantities at a time so that the temperature of the mixture remains between 60° and 70° shake the mixture vigorously after each addition of the diazo solution. Then fit a reflux air- or water-condenser to the flask, and heat the latter on a boiling water-bath for 15 minutes to complete the reaction. Finally steam-distil the solution until no more oily benzonitrile passes over (usually until about 600 ml. of distillate have been collected). 

From amines by the diazo reaction (see discussion preceding Section IV,59 p-tolumtrile and benzonitrile from p toluidine and aniline respectively, Section IV,66). 

Hydrolysis may be effected with 10-20 per cent, sodium hydroxide solution (see p-Tolunitrile and Benzonitrile in Section IV,66) or with 10 per cent, methyl alcoholic sodium hydroxide. For diflScult cases, e.g., a.-Naphthoniirile (Section IV,163), a mixture of 50 per cent, sulphuric acid and glacial acetic acid may be used. In alkahne hydrolysis the boiling is continued until no more ammonia is evolved. In acid hydro-lysis 2-3 hours boiling is usually sufficient the reaction product is poured into water, and the organic acid is separated from any unchanged nitrile or from amide by means of sodium carbonate solution. The resulting acid is identified as detailed in Section IV,175. 

The higjily water-soluble dienophiles 2.4f and2.4g have been synthesised as outlined in Scheme 2.5. Both compounds were prepared from p-(bromomethyl)benzaldehyde (2.8) which was synthesised by reducing p-(bromomethyl)benzonitrile (2.7) with diisobutyl aluminium hydride following a literature procedure2.4f was obtained in two steps by conversion of 2.8 to the corresponding sodium sulfonate (2.9), followed by an aldol reaction with 2-acetylpyridine. In the preparation of 2.4g the sequence of steps had to be reversed Here, the aldol condensation of 2.8 with 2-acetylpyridine was followed by nucleophilic substitution of the bromide of 2.10 by trimethylamine. Attempts to prepare 2.4f from 2.10 by treatment with sodium sulfite failed, due to decomposition of 2.10 under the conditions required for the substitution by sulfite anion. 

Conventional synthetic schemes to produce 1,6-disubstituted products, e.g. reaction of a - with d -synthons, are largely unsuccessful. An exception is the following reaction, which provides a useful alternative when Michael type additions fail, e. g., at angular or other tertiary carbon atoms. In such cases the addition of allylsilanes catalyzed by titanium tetrachloride, the Sakurai reaction, is most appropriate (A. Hosomi, 1977). Isomerization of the double bond with bis(benzonitrile-N)dichloropalladium gives the y-double bond in excellent yield. Subsequent ozonolysis provides a pathway to 1,4-dicarbonyl compounds. Thus 1,6-, 1,5- and 1,4-difunctional compounds are accessible by this reaction. 

Aryl, heteroaryl, and alkenyl cyanides are prepared by the reaction of halides[656-658] or triflates[659,660] with KCN or LiCN in DMF, HMPA, and THF. Addition of crown ethers[661] and alumina[662] promotes efficient aryl and alkenyl cyanation. lodobenzene is converted into benzonitrile (794) by the reaction of trimethylsiiyl cyanide in EtiN as a solvent. No reaction takes place with aryl bromides and chlorides[663]. The reaction was employed in an estradiol synthesis. The 3-hydroxy group in 796 was derived from the iodide 795 by converting it into a cyano group[664]. 

A mixture of l-(r-Boc)indol-2-yl-tri- -butylstannanc (1.2 mmol) and 4-bromo-benzonitrile (1.0 mmol) and Pd(PPh3)2C , (0.02 mmol) in dry dioxane (5 ml) was heated at I00°C overnight under nitrogen. The reaction mixture was cooled, diluted with EtOAc and stirred for 15 min with 15% aq. KF. The precipitate was removed by filtration and washed with EtOAc. The EtOAc layer was separated, washed with brine, dried (Na2S04) and concentrated. The residue was purified by chromatography on silica. The yield was 66%. 

Uses. The principal use of adiponitrile is for hydrogenation to hexamethylene diamine leading to nylon-6,6. However, as a result of BASE s new adiponitrile-to-caprolactam process, a significant fraction of ADN produced may find its way into nylon-6 production. Adipoquanamine, which is prepared by the reaction of adiponitrile with dicyandiamide [461-58-5] (cyanoguanidine), may have uses in melamine—urea amino resins (qv) (see "Benzonitrile, Uses"). Its typical Hquid nitrile properties suggest its use as an extractant for aromatic hydrocarbons. 

Reaction of benzonitrile A-oxide with alkynic phosphinate (343) gave exclusively 5-phosphinylisoxazole (344), whereas reaction with enamine phosphinate (345) gave the otherwise inaccessible 5-unsubstituted 4-phosphinylisoxazole (346) (80JOC529). 

Reaction of benzonitrile A-oxide with benzoylacetylene gave a mixture of 4-benzoyl-isoxazole (347) and 5-benzoylisoxazole (348), whereas that with )3-enaminone (349) gave exclusively 4-benzoylisoxazole (347) (71S433) and that with chloroenone (350) gave exclusively 5-benzoylisoxazole (348) (70S344). 

The reaction of benzonitrile A-oxide with a- and )3-azidostyrenes (351) and (352) gave 3,5- and 3,4-diphenylisoxazoles (353) and (354), respectively, in good yields (74JOC1221). Clearly, the X function has a pronounced directional effect on this type of 1,3-cycloaddition... 

Another type of (CNO-fC + C) reaction has been reported (77JCS(P1)1196). The reaction of dimethyloxosulphonium 4-nitrobenzylide (382) with benzonitrile iV-oxide gave 4,5-dihydro-4,5-bis(4-nitrophenyl)-3-phenylisoxazole (383) in 31% yield. So far, no synthetic utility for this reaction process has been reported. 

Diphenylisoxazole has been synthesized by the reaction of benzonitrile fV-oxide with /3-azidostyrene (352) (74JOCi22i). 

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