Pentyl cyanide

The structure is in part inferred from the observation that in boiling tetrahydrofuran the substance loses nitrogen and sulfur and gives pentyl cyanide. The absence of absorption in the neighbourhood of 2150 cm-1 indicative of an azide group excludes the thioacyl azide structure.17... 

It is remarkable that thermal decomposition in polar solvents (dimethyl formamide, tetrahydrofuran) gives pentyl cyanide whereas in a nonpolar solvent (decane, 150°) pentyl cyanide is formed together with pentyl isothiocyanate in a 4 1 molar ratio. The same ratio is obtained on injecting 5-pentylthiatriazole into glass wool heated at 350° in an evacuated flask. 

Cognate preparations. Hexanenitrile (pentyl cyanide). (Use of thionyl chloride.) Place 29g (0.25 mol) of hexanamide (Expt 5.154) in a 100-ml flask fitted with a reflux condenser, add 45 g (27.5 ml, 0.38 mol) of redistilled thionyl chloride and connect the top of the condenser to a gas absorption device... 

The results of kinetic measurements on the thermal decomposition of 5-alkoxythiatriazoles, studied by Jensen et al., are consistent with this scheme (76AHC(20)145, p. 149). The formation of pentyl cyanide and pentyl isothiocyanate in a 4 1 molar ratio from thermally decomposing 5-pentylthiatriazole (76AHC(20)145, p. 163) can apparently be rationalized along the same lines. 

Die Dehydrierung von aliphatischen sekundaren Aminen mit Benzolselenigsaure bzw. -anhydrid in Gegenwart von Natrium-cyanid oder von Cyan-trimethyl-silan verlauft uber eine Imin-Zwischenstufe, die durch Addition eines Cyanid-Ions stabilisiert wird2. Dies stellt einen neuen Weg zu a-Alkyl-amino-carbonsaure-nitrilen als Edukte entsprechender a-Alkylamino-carbonsaure-Derivate dar. Aus Dipentyl-amin erhalt man z. B. 2-Pentyl-am ino-hexansaure-am id 3 ... 

Michael addition of cyanide to both (+)- and (-)-carvone 1 has been studied in detail. All four possible products 2 can be obtained depending on the conditions, and it has been shown that 2 (P-CN, p-Me) is the kinetically controlled product, as first described by Lapworth in 1906. Reaction of 2 with pentyl nitrite in the presence of NaOEt/EtOH is strongly exothermic, and the temperature of the reaction mixture must be kept below 0°C. The product, formed in 62% yield, is the isoxazoloazepine 3. 

Pentanol (0.2 mol) was added to 1.8 ml water dissolved in toluene (80 g) and hydrogen chloride gas (0.4 mol) introduced. The temperature was lowered to 0°C, 2-(chloromethyl)-benzoyl cyanide (0.09 mol) added dropwise, and the mixture stirred 2 hours at ambient temperature. Thereafter, the mixture was heated to 60 °C 8 hours then cooled. It was extracted once with 50 ml of 15% strength HCl, 3 times with 50 ml water, dried, concentrated, and isolated in 95% yield but containing 4.99% of the impurity, pentyl... 

Euphococcinine and adaline (333) were synthesized from a 2-cyano-6-oxazolopiperidine [699], An anion at C(2) was condensed with 3-bromo-2-methoxy-l-propene, and after elimination of cyanide, the resultant iminium ion was alkylated with either a methyl- or pentyl-Grignard reagent to form the quaternary carbon. The second ring was closed with an intramolecular Mannich reaction. 

Phase-transfer hydrocarboxylation of terminal acetylenes 254 (R = Bu, pentyl, Ph or PhCH2CH2) with carbon monoxide, catalysed by nickel(II) cyanide, affords the alkenoic acids 255 Similarly, phenylacetylene reacts with carbon monoxide and alcohols in the presence of palladium(dibenzylideneacetone)2 to give esters of unsaturated acids, e.g. 256192. 

Carbonyl cyanide added dropwise during a few min. to a stirred soln. of n-pentyl mercaptan in light petroleum or hexane under Ng and anhydrous conditions, which are maintained throughout, kept 2 hrs. at room temp., then heated 10 min. on a steam bath to convert the intermediate dicyanohydrin product. Y 78%. F. e. s. M. T. Leplawy and A. Redlihski, Synthesis 1975, 504. 

If Ar = HiCO, a good yield of benzoyl cyanide is obtained. Allylic triphenyl-phosphonium halides react similarly with pentyl (isoamyl) nitrite and the products are decomposed by ethanolic potassium hydroxide to nitriles, for example, -methylcinnamonitrile is obtained in 57% yield and famesyl cyanide in 87% yield [127J. N-Nitroso compounds give nitriles on reaction with triphenylphos-phine alkylenes [128], for example... 

Phase Transfer Catalysis. The reactions of pentyl bromide with potassium cyanide under triphase reaction conditions were carried out as follows. The air-dried organo clay was dispersed in 3.0 mL aqueous solution of potassium cyanide in a 15 x 150 millimeter Pyrex culture tube equipped with a magnetic stirring bar and fitted with a Teflon screw cap. After the mixture was stirred for a few hours, 2.0 mmol of pentyl bromide and 0.5 mL n-decane as a chromatographic standard in 6.0 mL of toluene... 

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