Isonitriles Isocyanides

Sodium cyanide solution dissolves certain metals (I) with absorption of oxygen, e.g.. gold, silver, mercury, lead, and (2) with evolution of hydrogen, e.g.. copper, nickel, iron. zinc, aluminum, magnesium and solid sodium cyanide, when heated with certain oxides, e.g.. lead monoxide PhO. stannic oxide SnO.. yields the metal of the oxide, e.g.. lead. tin. respectively. and sodium cyanate NaCNO. Two classes of esters arc known, cyanides or nitriles, and isocyanides, isonitriles or carbylatnincs. the latter being very poisonous and of marked nauseating odor... 

Isocyanides (isonitriles or carbylamines) are formed in this reaction. 

Among the most widely used components for MCRs involving amines and carbonyls are the isocyanides (isonitriles) 26, which were initially used in the Pass-erini reaction [21] and more extensively in a series of MCRs introduced by Ugi (Scheme 7.4) [1, 5, 22], The great effectiveness of isocyanides in MCRs is apparently a result of their remarkable balance between nucleophilic and electrophilic reactivity that enables them to be relatively unreactive towards carbonyl compounds but quite reactive with activated derivatives such as the corresponding imi-nium species. Numerous applications of isocyanides in MCRs leading to a variety of novel multifunctional derivatives and heterocyclic systems have appeared in recent years [5-9]. 

IX dimethyl ester Pyz = Pyrazine RImH = Imidazole with an R substituent on one of the carbon atoms RNC = Alkyl or aryl isocyanide (isonitrile) RNO = alkyl or aryl nitroso compound RPy = Substituted pyridine RTPP = 7 -phenyl substituted tetraphenylporphyrin TCeTPP = Tetra-/3,/3 -tetramethylenetetraphenyl-porphyrin TMINP = Tetrakis(o-(methylisonicotinamidophenyl)porphyrin) T(o-M)PyP = Tetrakis(methyl-o-pyridinium)porphyrin ... 

The interests in homoleptic (see Homoleptic Compound) isocyanide ( isonitrile, see Isocyanide Ligands) complexes of transition metals have largely been associated with their similarities to metal carbonyls. The greater versatility of isocyanide ligands in comparison to CO makes isocyanide complexes potentially valuable reagents in synthetic chemistry and catalysis. The dication [V(CNBu )6] reported in 1980 remained the sole example of a homoleptic group 5 metal isocyanide until 1999, when the first binary... 

Isocyanides (Isonitriles). Phosgene in combination with triethylamine dehydrates monosubstituted alkylformamides to isocyanides (yields 60-80%). The mechanism... 

When an alkyl halide is treated with silver cyanide, reaction takes place in the usual way a silver halide and an organic compound are formed. The product, however, is not an alkyl cyanide, as is the case when potassium cyanide is used, but an isomeric compound. The substances prepared from silver cyanide are called isocyanides, isonitriles, or carbylamines. The last name is given to them on account of the fact that they unite with acids and thus resemble the amines. The addition-products do not, however, resemble salts in their chemical properties. When hydrogen chloride is passed into an ethereal solution of methyl isocyanide, a compound of the formula 2CH3NC.3HCI is formed, which is decomposed when brought into contact with water. 

Both potassium and sodium cyanide react with alkyl halides to give excellent yields of the nitrile in the solvent DMSO. When the reaction is done in refluxing alcohol or when certain other metal cyan-ides are used, an isomeric product (see 4) is often observed called an isonitrile (isocyanide). Isonitriles were first reported... 

Isocorypalmine see protoberberine alkaloids. Isocyanides (isonitriles, natural). 

In 1874 Sell and Zierold obtained phenylcarbonimidoyl dichloride I in the reaction of phenylisothiocyanate II with chlorine. Several years later, Nef ( 8,109 prepared carbonimidoyl dichlorides by addition of chlorine to isocyanides, such as phenyl isocyanide III. This relationship between I and isocyanides (isonitriles) led to the frequently used term isocyanide dichlorides for the compounds under discussion. 

The reaction of isocyanides (isonitriles) with carboxylic acid chlorides gives rise to the formation of imidoyl chloride derivatives LVl... 

Isocyanides (isonitriles), RNC, are isoelectronic with carbon monoxide, CO. Most commonly, they coordinate to the metal through the carbon atom, although many complexes are also known in which the RNC molecule is bonded to metal atoms through both the carbon and nitrogen atoms.Isocyanides may coordinate to metal atoms in the following way ... 

Immonium ions, R2N = CR2 xxxxxxxx Covalent isocyanides (isonitriles), R - NC xxxxx I Covalent cyanates, R- O-CN xxx... 

Isocyanide (Isonitrile) and Diazoalkane Complexes 7.02.2.3.1 Binary complexes... 

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