Thioamides conversion into nitriles

Bis(p-methoxyphenyl) tellurium diacetate or ditosylate is generated by the electrolysis of the parent telluride in the presence of BU4N+ acetate or tosylate. Like the telluroxide, they accomplish the conversion of thioamides into nitriles and 1,2,4-thiadiazoles. Taking into consideration of these facts, the above conversion can be performed in an electrochemical... 

A popular reaction type in recent years has been the conversion of alcohols into other compounds by use of an organophosphorus compound in the presence of a source of a nucleophile [reaction (8)]. PhsP plus diethyl azodicarboxylate has been a particularly popular form of organophosphorus reagent, and the product is formed with inversion of configuration. In 1977 there appeared a number of variations on this general theme, for the synthesis of halides, thiocyanates, thio-ethers, azides, and esters from alcohols.Similar systems have been used to convert amides and thioamides into nitriles. ... 

The dehydration of amides is one of the most important methods for the preparation of nitriles, and many reagents are known to effect this transformation. Two new reagents have now been reported " which significantly add to the available methodology. In one, amides (and thioamides) undergo conversion into the corresponding nitriles when treated with cyanuric chloride in DMF solution at room temperature (Scheme 22). In the other, " the preformed Vilsmeier reagent (16) and pyridine in DMF also effect the dehydration within minutes at 0°C this method is especially useful for the synthesis of a ,/3-unsaturated nitriles (Scheme 23). 

Aminoisothiazolo[3,4-b]pyridine (138) is formed from 2-aminonicotino-nitrile (137) by its successive conversion into the thioamide and oxidative... 

Several examples exist for the conversion of 5-aminothiazoles into the corresponding thiazolopyrimidines. Shaw and Butler report the formation of aminothiazole thiocarboxyamide 27 from the thioamide 26 and carbon disulphide using Cook and Heilbron s procedure. Methylation of 27 gave carboxythioimidate 28 which then reacted with sodium hydroxide to give amino-nitrile 29, and with formic acid and acetic anhydride to give the thiazolopyrimidine 30. 

This reaction has recently been applied with success5 s for the modification of poly-(a-chloroacrylonitrile). As reported by the authors, the level of conversion of the nitrile groups into thioamide groups reaches 90%. 

Fig. 5. Effect of the nature of adjacent functional groups in copolymers on the rate of conversion of the nitrile groups into thioamide groups. (1) PAN (2) AN-VDC (3) AN-AA (4) AN-MA (5) AN-VC (6) AN-ST...

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