Ethyl isocyanate

The nitrogen of aHphatic and aromatic amines is alkylated rapidly by alkyl sulfates yielding the usual mixtures. Most tertiary amines and nitrogen heterocycles are converted to quaternary ammonium salts, unless the nitrogen is of very low basicity, eg, ia tn phenylamine. The position of dimethyl sulfate-produced methylation of several heterocycles with more than one heteroatom has been examined (22). Acyl cyanamides can be methylated (23). Metal cyanates are converted to methyl isocyanate or ethyl isocyanate ia high yields by heating the mixtures (24,25). 

Naphthyl)ethyl isocyanate 2 for chromatographic resolution of alcohols, hydroxy esters thiols via diastereomenc derivatives. 

Alkyl uracyls have been known for some time to act as diuretic agents in experimental animals. The toxicity of these agents precluded their use in the clinic. Appropriate modification of the molecule did, however, yield diuretic agents with application in man. Reaction of allylamine with ethyl isocyanate affords the urea, 89 (the same product can of course be obtained from the same reagents with reversed functionality). Condensation with ethyl cyanoacetate affords aminotetradine (90). In... 

To a cooled and stirred solution of 142 parts of methallylamine in 900 parts of benzene, 156 parts of ethyl isocyanate are added dropwise. Upon concentration in vacuum N ethyl-N -methallylurea Is obtained. 

A series of reactions was developed to transfer amines to ureido- and thioureido-derivatives for separation. The reaction of ureido-derivatives is widely used by the reaction with 1-phenylethyl isocyanate (PEIC) [8] or the naphthyl-analogue 1-(1-naphthyl)ethyl isocyanate (NEIC) [9]. Both reactions can be used not only for chiral amines but also for alcohols and thiols. 

If 5ym."diethylurea is heated with aniline, the gaseous ethylamine which results from the dearrangement escapes and the ethyl isocyanate combines with the less volatile aniline to form sym.-ethylphenylurea. This substance can now dearrange into two modes. 

The solid explodes on attempted drying. DTA indicates that the rapid decomposition at 70-74°C to potassium hydroxide and ethyl isocyanate, accompanied by an exotherm of 1.37 kJ/g, is involved in the explosion. 

Dimethylphenylthiourea, 46, 70 Dimethylphosphine, 46, 103 Dimethylphosphinic acid, 46, 103 Dimethylphosphinyl chloride, 46, 103 N,N-Dimethyl-l,3-propanediamine, reaction with ethyl isocyanate, 48, S3... 

Ethyl formate, condensation with 2-methylcydohexanone, 48, 41 purification of, 48, 42 Ethyl isocyanate, reaction with N,N-dimethy 1-1,3-propanediamine,... 

A. l-Ethyl-3-(3-dimethylamino)propylcarbodiimide. A solution of 100 g. (1.41 moles) of ethyl isocyanate (Note 1) in 750 ml. of methylene chloride is prepared in a 5-1. three-necked flask equipped with a mechanical stirrer, an immersion thermometer, and a 500-ml., pressure-equalizing, addition funnel (Note 2). The flask and its contents are cooled to 5° in an ice bath, and a solution of 144 g. (1.41 moles) of N,N-dimethyl-l,3-propanedi-amine in 250 ml. of methylene chloride is added through the addition funnel at a rate such that the reaction temperature does not exceed 10° (Note 3). On completion of this addition 500 ml. of triethylamine is added to the flask, and a solution of 300 g. (1.6 moles) of -toluenesulfony 1 chloride in 300 ml. of methylene chloride is placed in the addition funnel and added to the reaction... 

N-Methylethylamine has been prepared by heating ethyl-amine with methyl iodide in alcohol at 100° 3 by the hydrolysis of N-methyl-N-ethylarenesulfonamides,4-5 -nitroso-N-methyl-N-ethylaniline,6 or methylethylbenzhydrylidene ammonium iodide 7 by catalytic hydrogenation of ethyl isocyanate or ethyl isocyanide 8 and by the reduction of ethyl isocyanate by lithium aluminum hydride,9 of N-methylacetisoaldoxime by sodium amalgam and acetic acid,10 or of a nitromethane/ethylmagnesium bromide adduct by zinc and hydrochloric acid.11... 

Naphthyl)ethyl isocyanate, chiral derivatizing reagent, 6 76t 1-Naphthyl-Al-methylcarbamate, 17 84 Napierian absorbance, 23 126 Naples yellow, 14 792 Napping, of staple-fiber non woven fabrics, 17 515... 

The hydroxy derivatives on reaction with ethyl isocyanate in the presence of CuCl in THF gave the corresponding carbamate lactones. 

Saito et ai, this principle was then applied by Molina and his group to a broad range of molecules (94S1197). Thus, diazide 340 was transformed via a Staudinger reaction to bisiminophosphorane 341 with partial cyclization to l//-l,2,4-triazolo indazole (Scheme 124). Treatment with ethyl isocyanate leads to a pentacyclic 1,3,5-benzotriazepine (343) in 52% yield. With other isothiocyanates the yield can be improved to 82% (91TL2979 92T3091 94S1197). 

Numerous synthetic routes to the dinitramide anion have been reported. Cesium dinitramide (149) has been synthesized via the fluoride-catalyzed /1-elimination of 1-(V,A1-dinitramino)-2-trimethylsilylethane (148) with cesium fluoride the latter prepared by treating 2-(trimethylsilyl)ethyl isocyanate with a solution of nitronium tetrafluoroborate and pure nitric acid in acetonitrile. ... 

New examples of the formation of pyrazolo[3,4-r/ [l,2,3]triazoles from 4-aminopyrazoloureas, described above in Section 10.05.9.1.2(vii)), have been described. The recent publication of Maggio and co-workers provides an insight into the mechanism of the reaction. It has been shown that nitrosation of 230 with nitrous acid at 0°C followed by adjustment of the pH to 8 and room temperature extraction furnishes, from amongst a mixture of products, the 5,5-bicycle 231 whilst extraction and work-up at 0°C yielded the 5,7-bicycle 232 as the single reaction product. The latter is the precursor to the pyrazolotriazole which results simply from room temperature solution decomposition involving loss of (m)ethyl isocyanate. The formation of the triazole 231 from the tetrazepinone 232 is rationalized as shown in Scheme 48 <2006ARK120>. 

Another useful reagent for alcohols is Pirkle s (-)-(/ )-l-(l-naphthalenyl)ethyl isocyanate (14)161. For example, it was used to separate the two diastereomeric carbamates obtained from rue-13. The carbamate shown by X-ray analysis to have structure 15 was cleaved162 to furnish (+ )-strigol (13), the witchweed germination factor, thus confirming the absolute configuration of 13163. 

The photodissociation spectra of the Mg(L) complexes of ethyl isocyanate and ethyl isothiocyanate show some common photofragments. Aside from the ubiquitous formation of Mg+ (cf equation 39), both ethyl isocyanate and ethyl isothiocyanate yield products from attack of the N—C single bond (equations 57 and 58). The ethyl isothiocyanate complex also yields MgS via equation 59. The photodissociation spectrum of the ethyl thiocyanate isomer was also examined and gave the products shown in equations 60-62. Thus each isomer gives a unique ionic product [Mgs for ethyl isothiocyanate (equation 59) vs MgNC+ for ethyl thiocyanate (equation 62)] which allows their distinction. Finally, the Mg(ethyl isocyanate) +" complexes simply undergo solvent evaporation for n = 2 and 3 (cf equation 52). 

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