CARBYLAMINE REACTION

Give the isocyanide (carbylamine) reaction, if the anilide is an acylated primary amine. 

Isocyanide (or carbylamine) reaction. Dissolve 1 ml. of chloroform in 2-3 ml. of alcoholic NaOH solution, add a few drops of aniline, mix well and warm gently the foul odour of isocyanide is produced. 

The versatility of this method for the alkylation of compounds containing active methylene groups is illustrated by Table I. Review articles have recently appeared,34 and the application to the Hofmann carbylamine reaction is described in the following procedure in this volume, p. 96. 

HOFMANN CARBYLAMINE REACTION te ft-BUTYL ISOCYANIDE (2-Methylpropane, 2-isocyano)... 

Various synthetic routes to isocyanides have been reported since their identification over 100 years ago.8 Until now, the useful synthetic procedures all required a dehydration reaction8-11 Although the carbylamine reaction involving the dichlorocarbene intermediate is one of the early methods,8 it had not been preparatively useful until the innovation of phase-transfer catalysis (PTC).4 5... 

Carboxylic acids, a-bromination of 55, 31 CARBOXYLIC ACID CHLORIDES, ketones from, 55, 122 CARBYLAMINE REACTION, 55, 96 Ceric ammonium nitrate [Ammonium hexa mtrocerate(IV)[, 55, 43 Chlorine, 55, 33, 35, 63 CHROMIUM TRIOXIDE-PYRIDINE COMPLEX, preparation in situ, 55, 84 Cinnamomtnle, a-phenyl- [2-Propeneni-tnle 2,3-diphenyl-], 55, 92 Copper(l) iodide, 55, 105, 123, 124 Copper thiophenoxide [Benzenethiol, copper(I) salt], 55, 123 CYCLIZATION, free radical, 55, 57 CYCLOBUTADIENE, 55, 43 Cyclobutadieneiron tricarbonyl [Iron, tn-carbonyl(r)4-l,3-cyclo-butadiene)-], 55,43... 

Aliphatic and aromatic primary amines on heating with ehloroform and ethanolic potassium hydroxide form isocyanides or earbylamines which are foul smelling substances. Secondary and tertlaiy amines do not show this reaction. This reaction is known as carbylamine reaction or Isocyanlde test and Is used as a test for primary amines. 

Carbon monoxide, 57, 11 Carbonyl compounds, 56, 36 Carboxylic acids, a-bromination of, 55, 31 CARBOXYLIC ACID CHLORIDES, ketones from, 55, 122 CARBYLAMINE REACTION, 55, 96 Carcinogens, list of. 56, 128 58, 168 Carveol, 56, 106 Carveol acetate, 56, 106 Catechols, 58, 125... 

Finally, it should be remembered that isonitriles are not only obtained by substitution processes, but also by alternate routes, which may be of high value. In particular the various techniques for the dehydration of formamides, or the phase transfer version of the classical carbylamine reaction should be noted. ... 

The presence of aniline is shown by the carbylamine reaction. Aniline and monomethylaniline react with acetic anhydride. An approximate estimate can be obtained by the rise of temperature when 50 c.c. of the dlmethylaniline and 10 c.c. of acetic anhydride are brought together in a Dewar vessel. A comparative experiment should be made with dimethylaniline containing a known amount of monomethylaniline. Alternatively the amount of acetic anhydride used up may be determined by filtration. A weighed quantity of acetic anhydride (about 2 5 g.) is added to a weighed quantity of dimethyl-aniline (about 10 g.). The acetylation is allowed to proceed for two to three hours, 70 c.c. of water added and the whole warmed on a water-bath for half an hour and then titrated with sodium hydroxide. This gives the quantity of acetic anhydride not used in acetylation. 

Amino-4,6-bis(dimethylamino)-l,3,5-triazine has been converted by the Hofmann carbylamine reaction under phase-transfer conditions into 4,6-bis(dimethylamino)-2-isocyano-l,3,5-triazine... 

As some methyl cyanide is formed in the reaction, the substance is best prepared by heating methylamine with an alcoholic solution of chloroform and potassium hydroxide (carbylamine reaction, section 206) —... 

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