Alkyl nitrites isoamyl nitrite

The thiazolyl radicals are, in comparison to the phenyl radical, electrophilic as shown by isomer ratios obtained in reaction with different aromatic and heteroaromatic compounds. Sources of thiazolyl radicals are few the corresponding peroxide and 2-thiazolylhydrazine (202, 209, 210) (see Table III-34) are convenient reagents, and it is the reaction of an alkyl nitrite (isoamyl) on the corresponding (2-, 4-, or 5-) amine that is most commonly used to produce thiazolyl radicals (203-206). The yields of substituted thiazole are around 40%. These results are summarized in Tables III-35 and ni-36. 

Electrophilic substitution of the ring hydrogen atom in 1,3,4-oxadiazoles is uncommon. In contrast, several reactions of electrophiles with C-linked substituents of 1,3,4-oxadiazole have been reported. 2,5-Diaryl-l,3,4-oxadiazoles are bromi-nated and nitrated on aryl substituents. Oxidation of 2,5-ditolyl-l,3,4-oxadiazole afforded the corresponding dialdehydes or dicarboxylic acids. 2-Methyl-5-phenyl-l,3,4-oxadiazole treated with butyllithium and then with isoamyl nitrite yielded the oxime of 5-phenyl-l,3,4-oxadiazol-2-carbaldehyde. 2-Chloromethyl-5-phenyl-l,3,4-oxadiazole under the action of sulfur and methyl iodide followed by amines affords the respective thioamides. 2-Chloromethyl-5-methyl-l,3,4-oxadia-zole and triethyl phosphite gave a product, which underwent a Wittig reation with aromatic aldehydes to form alkenes. Alkyl l,3,4-oxadiazole-2-carboxylates undergo typical reactions with ammonia, amines, and hydrazines to afford amides or hydrazides. It has been shown that 5-amino-l,3,4-oxadiazole-2-carboxylic acids and their esters decarboxylate. 

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. 

In a communication by Tanimoto and coworkers, ketene O-alkyl O -trunethylsilyl acetals 49 provide either a-nitroso esters 50 or their oximes 51 on reaction with nitric oxide or isoamyl nitrite in the presence of titanium(IV) chloride (Scheme 29). These reactions seem to provide a relatively direct way to introduce a nitrogen substituent at the a-carbon atom of carboxylic esters. 

Amyl nitrite is generally sold in small glass bottles or, in rare cases, small vials or ampoules. It is chemically related to nitroglycerine. It is part of a group of closely related chemicals known as alkyl nitrites. In street terminology, amyl, butyl, isobutyl, isoamyl, isopropyl, and cyclohexyl nitrates and nitrites are collectively... 

The addition of an alkyl nitrite (e.g., isoamyl nitrite) as a promoter in the aerial oxidation of cyclohexane in the presenceofaCo/Mncatalystled to an improvement in the conversion and in the selectivity to Ol/One and AA, compared to the unpromoted reaction [7nj. For instance, at 120 °C and 9 atm oxygen pressure, 9.7% cyclohexane conversion was obtained in 3 h reaction time, with selectivity to 01/Oneof65%andto AA of 35%. In the absence of the nitrite, the conversion was less than 4%. 

A conversion of alkyl halides to oxime derivatives was proposed by Murphy [56], Irradiation of iodides or activated bromides in the presence of isoamyl nitrite and hexabutylditin afforded the corresponding oxime. Interestingly, this reaction is suitable for cyclization-nitrosation cascade reactions (Scheme 20). 

Alkylation with methyl iodide or trialkyloxonium fluoborate occurs with some difficulty by analogy with 5-amino-l,2,4-thiadiazoles,74 the products are formulated as N4 quaternary salts. The 5-methyl group (in 392) readily undergoes condensation with aromatic aldehydes to 5-styrylthiadiazoles (393). The action of carboxylic acid esters gives ethoxalyl derivatives (394) and that of isoamyl nitrite produces the oxime (395).287... 

Phosphorylation. The compound reacts with an alcohol or a phenol at 0° in pyridine to form O-alkyl-O-phenyl N-phenylphosphoromidates (2) in 70-867o yield. The aniline group in (2) is removed by treatment with isoamyl nitrite (excess). ... 

The modifications of the Knoevenagel diazotization method include the addition of isoamyl nitrite to an appropriate amine salt suspended in cold acetic acid and the diazotization of amine by the addition of a solution of N2O4 in ether. In addition, a specific method for the preparation of anhydrous diazonium tetrafluoroborate has been developed in which the amine is mixed with an alkyl nitrite and an excess amount of BF3 Et20. For this preparation, the excess BF3 can trap the alcohol and water produced during the diazotization, and the diazonium tetrafluoroborate precipitates from the reaction solution as it is formed. ... 

NH,N0g Alkyl-, Butyl-, Amyl-, Isoamyl nitrite p-ClCgHfiO-ONO NO2-NO BF -NOCl, NOBr Alkyl nitrate, Ethyl -, Amyl -Acetyl-... 

Isoamyl nitrite j titanium tetrachloride a-Oximinocarboxylic acid esters from O-silyl O-alkyl keteneacetals... 

TiCl4 added dropwise to a stirred soln. of startg. O-silyl O-alkyl keteneacetal and isoamyl nitrite in methylene chloride at 10°, and stirring continued at room temp, for 24 h ethyl a-oximinopropionate. Y 65%. O-Silyl O-alkyl keteneacetals not possessing an a-hydrogen gave a-nitrosocarboxylic acid esters. F.e. and with nitric oxide s. S.M. Ali et al., Synthesis 1988, 805-6. 

Alkyl-, Butyl-, Amyl-, Isoamyl nitrite p-ClCgHfiO-ONO NOg-... 

A new method for the conversion of imino to carbonyl groups via nitrosoimines has been published. S-Alkyl thiocarbamates are thus obtained from isothiouronium salts with isoamyl nitrite under mild conditions... 

Isoalloxazines 15, 356 Isoamyl nitrite s. Alkyl nitrite Isobornyloxymagnesium bromide s. Magnesium bromide, isobornyloxy-Isobutenyl ketones... 

Trialkylboranes transfer an alkyl group to ethyl acrylate or methacrylate in a Michael sense under electrolytic conditions to give saturated esters in 51—94% yields.Simple Grignard reagents can be converted directly into esters in 70—80% yield by sequential treatment with pentacarbonyliron and an alcohol saturated with iodine the presumed intermediates are acyltetracarbonylfer-rates. An aprotic deamination of primary amines with isoamyl nitrite in the presence of a carboxylic acid also leads directly to esters. 

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