Nitriles from isonitriles

Fluorine-substituted quinolines can be formed in good yields from readily available starting materials. The reaction proceeds by generating nucleophiles through addition to multiple bonds, in this case, nitriles and isonitriles <03OL1455>. 

Triple bonds add azides to give 1,2,3-triazoles (from carbon-carbon triple bonds) and tetrazoles (from nitriles or isonitriles). The reactions are of very wide scope, but there are few examples involving acyl azides. The formation of triazoles from acetylenes and azides in general has been reviewedand the scope of these reactions has been expanded by more recent work, a few examples of which are found in the references 255-25s triazole formation from acetylenes... 

Adducts (6) and (7) from amides and chlorophosphoric acid aiyl esters or dichlorophosphoric acid aryl esters respectively are well known. - The adducts are formed in a 1 1 ratio. They have been applied to the synthesis of mixed anhydrides from diarylphosphoric acids and carboxylic acids, as well as mixed substituted esters of pyrophosphoric acid. The adduct formation between primary or secondary carboxamides and dichlorophosphates has been used to prepare nitriles and isonitriles respectively. The adduct from DMF and phenyldichlorophosphate is a useful reagent for the preparation of carboxylic acid esters from the corresponding acids and alcohols, 3-lactams from imines and carboxylic acids," carboxylic acid anhydrides, carboxylic acid esters and thiol esters. Adducts of amides with ester amides or diamides of chlorophosphoric acid have been studied. ... 

A still unresolved problem is the structure of the often used adducts from phosphorus trihalides and carboxylic acid amides, which might be described by the formulae (8) or (9). With the aid of in situ generated adducts of acid amides and PX3 amidines, isonitriles, quinazolinones, alkyl chlorides, aminomethylenediphosphonic acids, carbamoyl halides, triformylaminomethane, 1,3,4-oxadia-zoles, sulfides (from sulfoxides), nitriles (from primary nitro compounds)" and bromoqui-nolines (from methoxyquinolines)" have been prepared. 

In both the nitrile and isonitrile complexes rapid reaction techniques indicate that protonation occurs at the ligand initially, but subsequent rearrangement yields a metal-hydride product. However, in both cases protonation is at the atom remote from the metal and so the transfer from ligand to metal must involve the proton either (i) sliding down the ligand or (ii) sequentially hoping from one atom to another as shown in the Figures 28 and 29. 

With cyanide as the nucleophile, 1,4-DCB yields 4-cyanophenylsubstituted cyanoalkanes from a variety of alkenes and dienes. Highest yields are obtained when the alkene or diene has an oxidation potential <1.5 V vj. SCE. Both nitriles and isonitriles are obtained from the alkenes studied whereas only nitriles were detected from conjugated dienes. With fluoride ion, 4-cyanophenylsubstituted fluoroalkanes were obtained from alkenes but not from conjugated dienes. 

Beside all described syntheses of tetrazoles from nitriles and azides, l-sub-stituted tetrazoles, which are synthesized from isonitriles, have also received much attention [177-179]. 

Triphenylphosphine dibromide is a versatile dehydrating agent for amides. Depending on the starting material, nitriles, carbodiimides, isonitriles, or keteneimines may be obtained. Silicon tetrachloride is a useful coupling agent for amide formation, since it is converted to silica, easily separable from other reaction products. ... 

Nitrile and isonitrile compounds were prepared by the reaction of complexes [Re(CO)3(N-RIm)2(OTf)] with pivalonitrile or ferf-butylisocyanide and the salt NaBAr 4 in dichloromethane. Employing the latter as a triflate abstractor is based on the low solubility of sodium triflate in dichloromethane and is needed to achieve the displacement of triflate from the cationic complex by the poor donor nitrile, or by the low-nucleophilic isonitrile. 

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