W-Butyl nitrite

Isopropyl nitrite may be prepared according to the procedure given for w-butyl nitrite.1... 

The w-butyl nitrite must be refrigerated after preparation3 and used as soon as possible thereafter. The use of commercially available w-butyl nitrite invariably led to lower yields of the isocarbostyril. 

After about fifteen minutes, the theoretical amount of freshly distilled w-butyl nitrite (95 g. for every 100 g. of phenylhydroxylamine) is added slowly through a dropping funnel (Note 3). The addition of butyl nitrite usually requires about one hour (Note 4), during which time the stream of ammonia gas is continued in order that ammonia may always be in excess. If this precaution be not observed, a colored product will result. The temperature of the reaction mixture should bo maintained below io° and this may be done best by controlling the rate at which the butyl nitrite is added. An appreciable rise in tem-... 

Diazo-A-norcholestan-l-one (114) is prepared from 5y -2-oximino-A-norcholestan-l-one (113) with chloramine in aqueous ether in 63% overall yield.20,43"45 Steroidal ketones 115 and 118 (D-ring and A-ring) are converted to the corresponding diazoketones 117 and 120 via ketoximes 116 and 119 using chloramine with w-butyl nitrite and /-BuOK in 55% and 78% yields, respectively.46... 

The checkers used commercially available -butyl nitrite and experienced no difficulty in removing the w-butyl alcohol. 

The submitters used amyl nitrite U.S.P. from Mallinckrodt Chemical Works isoamyl nitrite supplied by Matheson, Coleman and Bell is apparently the same material. They found that other alkyl nitrites (ethyl, w-butyl, 1-butvl, amyl) may be used with equal success. Subsequent to the checking of this procedure, they reported that the amount of nitrite can be reduced to a 20% molar excess. 

Diazonium ions generated from ordinary aliphatic primary amines are usually useless for preparative purposes, since they lead to a mixture of products giving not only substitution by any nucleophile present, but also elimination and rearrangements if the substrate permits. For example, diazotization of n-butylamine gave 25% 1-butanol, 5.2% 1-chlorobutane, 13.2% 2-butanol, 36.5% butenes (consisting of 71% 1-butene, 20% fra/w-2-butene, and 9% cir-2-butene), and traces of butyl nitrites.351 ... 

In a 3-I. three-necked, round-bottomed flask fitted with a mechanical stirrer (Note i), a separatory funnel extending to the bottom of the flask, and a thermometer, are placed 380 g. (5.5 moles) of c.P. sodium nitrite and 1.51. of water. The flask is surrounded by an ice-salt mixture and the solution stirred until the temperature falls to 0°. A mixture of 100 cc. of water, 136 cc. (250 g., 2.5 moles) of concentrated sulfuric add (sp. gr. 1.84) (Note 2), and 457 cc. (370 g., 5 moles) of commercial w-butyl alcohol is cooled to 0°, and by means of the separatory funnel is introduced slowly beneath the surface of the nitrite solution, with stirring. The alcohol solution is added slowly enough so that practically no gas is evolved, and the temperature is kept at 1°. This usually requires from one and one-half to two hours. 

DL-Isoleucine is synthesized in about 56% over-all yield by the method of Hamlin and Hartung (366). o-Oximino- -methyl-w-valeric acid (A) is prepared in 70% yield from ethyl sec.-bulyl acetoacetate, butyl nitrite and sulfuric acid. DL-Isoleucine is prepared in 80% yield by the reduction of (A) with hydrogen, palladium chloride and ethanol. This method is essentially the same as that originated by Bouveault and Locquin (117, 118, 525). By the comparable procedure of Feofilaktov (264, 265) the phenylhydrazone of methyl ethyl pyruvic acid, prepared from sec.-butyl acetoacetate and phenyldiazonium chloride (aniline and NaN02) in 68% yield, is reduced by means of rinc and alcoholic HCl to nearly the theoretical yield of a mixture of DL-isoleucine and DL-allo-isoleucine. Ehrlich (235) synthesized a mixture of isoleucine and allo-isoleucine from 2-methyl-n-butyraldehyde by the Strecker reaction. 

Mendenhall, G., Golden, D. M., Benson, S. W., The Very-Low-Pressure P olysis (VLPP) of n-Propyl Nitrate, ter-Butyl Nitrite, and Methyl Nitrite, Rate Constants for Some Alkoxy Radical Reactions, Int. J. Chem. Kinetics (1975) X>... 

Castle, K.J., J. Abbott, X. Peng, and W. Kong (2000), Photodissociation of f-butyl nitrite between 220 and 250 nm Internal energy distribution of NO, Chem. Phys. Lett., 318, 565-570. 

A soln. of di-n-butyl-N-methylphosphoramidate in chloroform containing 1.5 moles amyl nitrite treated at 0° with a strong acid, such as HCl, in an organic solvent, and allowed to stand at room temp. di-n-butyl hydrogen phosphate. Y 90-95%. F. e. s. W. J. Hopwood, P. D. Regan, and J. A. Stock, Proc. Chem. Soc. 1964, 394 Soc. (C) 1966, 640. 

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