Methyl isonitrile isomerization

Cyanomethane, commonly known as acetonitrile, CH3CN, is a toxic volatile liquid that is used as a solvent to purify steriods and to extract fatty acids from fish oils. Acetonitrile can be synthesized from methyl isonitrile by the isomerization reaction CH,NC(g) - CH3CN(g). 

The isomerization of methyl isonitrile (CH3NC) to acetonitrile (CH3CN) was studied in the gas phase at 215 °C, and the following data were obtained ... 

Figure 14.9 Pressure of methyl isonitrile as a function of time. Two successive half-lives of the isomerization reaction (Figure 14.6) are shown. 

A Figure 14.15 Energy profile for the rearrangement (isomerization) of methyl isonitrile. The molecule must surmount the activation-energy barrier before it can form the product, acetonitrile. 

CQ cule) reaction, such as the isomerization of methyl isonitrile (Rgure 14.6), in terms of the collision model, (b) In... 

Palladium-mediated cydization based on the reactivity of o-alkynyl or alkenyl-phenyl isonitriles have been developed [105]. On the basis of their earlier studies on the three-component synthesis of allyl aryl cyanamides [106], Yamamoto and co-workers reported a palladium-catalyzed three-component coupling reaction of 2-alkynylisocyanobenzenes 122 with allyl methyl carbonate and trimethylsilylazide leading to N-cyanoindoles 125 [107]. One of the key steps of the proposed mechanism is the formation of 7i-allylpalladium carbodiimide 123 and its isomerization to rc-allylpalladium cyanamide complex 124 (Scheme 8.50). 

Nucleophilic attack at the carbon of a coordinated isonitrile molecule in the complex cations [7r-C5H5Fe(CO)3, j(CNMe),(] (x = 1, 2) using QFjLi produced inter alia the imino derivatives [7r-C5H5Fe(CO)(L)C(C5F5)= NMe] (L = CO, CNMe). Chromatographic separation of the products gave the complex (L = CNMe) in two isomeric forms, shown by IR spectroscopy to arise from cis or trans orientation of the Al-methyl group... 

Iso-nitriles, Carbylamines.— The alkyl cyanides because of tlieir relations to acids are known as acid nitriles methyl cyanide by hydrolysis yields acetic acid and it is thus known also as acetic nitrile. The iso-cyanides being isomeric with the nitriles are also termed isonitriles. Another name is sometimes used because of. their amine relationship, viz., carbyl-amine methyl iso-cyanide, CH3—NC, being methyl carbylamine. The lower alkyl-iso-cyanides are liquids with a very strong disagreeable odor. They are readily hydrolized by water but form salts with hydrochloric acid and also with silver cyanide. 

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. 

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