P-toluenesulfonyl cyanide

The imidazopyridine 123 was synthesized by treating amino acid 122 with p-toluenesulfonyl cyanide and DCC. The yield of 123 was lower (38%) when the mtinchnone was generated with mesyl chloride (72). The minor amide product 124 is proposed to arise from the diastereoisomeric mtinchnone adduct that undergoes fragmentation rather than decarboxylation. 

Titanium(IV) isopropoxide, 92-95, 99 Titanocene dichloride, 163, 164 p-Toluenesulfinyl chloride, 8 p-Toluenesulfinylimidazolide, 535 p-Toluencsulfonic acid, 535 p-Toluenesulfonyl azide, 535-536 p-Toluenesulfonyl chloride, 536 p-Toluenesulfonyl cyanide, 536 /7-Toluenesulfonylhydrazine, 537... 

Weigh the p-toluenesulfonyl cyanide into the second two-necked flask, flush with argon, and dissolve in THF (5 mL). 

Add the p-toluenesulfonyl cyanide solution to the solution of the organozinc halide at-78°C. 

Lithio-benzothiophenes can be generated, and reacted with electrophiles, if the temperature is kept low. ° Direct deprotonation of benzothiophenes follows the usual pattern for flve-membered heterocycles and takes place adjacent to the heteroatom,"" and in concord with this pattern, metal-halogen exchange processes favour a 2- over a 3-halogen the sequence below shows how this can be utilised to develop substituted benzothiophenes. 2-Lithiated reagents react with electrophiles for example with p-toluenesulfonyl cyanide, 2-cyano derivatives are produced and similarly, 2-trimethylstannylbenzofuran and -benzothiophene and benzofuran-2- and benzothiophene-2-boronic acids can be prepared. 

A three-necked flask was charged with 5-chloro-l-iodo-l-pentene (1.8 g, 6.0 mmol) in THF (5 mL) and was cooled to — 100°C (liquid N2/ether bath), and n-BuLi (6.3 mmol, 1.6M in hexane) was added over 4 min. The resulting colorless solution was stirred at 0°C for 2min and cooled back to -78 °C. p-Toluenesulfonyl cyanide (0.90g, 5.0 mmol) in THF (5 mL) was added and the reaction mixture was warmed to room temperature and stirred for 3 h. After the usual workup and evaporation of the solvents, the crude residue obtained was purified by flash chromatography (hexane/ether, 10 1), yielding the unsaturated nitrile 10 (466 mg, 72% yield) as a clear oil (100% by GLC analysis and l3C NMR analysis). 

Additional general methods for the synthesis of 7V-sulfonyl-imines based on the in situ generation of 0-sulfinate derivatives of oximes employing sulfinyl chlorides (phenyl- and methyl-sulfinyl chloride) or sulfonyl cyanides (p-toluenesulfonyl cyanide) and their subsequent rt rearrangement have been detailed. 

The Diels-AIder reaction is one of the more powerful reactions in all of organic chemistry. A Diels-AIder strategy can be used to prepare cyclic amino acids. Dienes can react with tosyl cyanide to generate lactams. Cyclopentadiene reacted with p-toluenesulfonyl cyanide (N-tosyl cyanide TsCN MeC6H4S02CN), for example, to give azabicycloheptene derivative, 7.772.100 Treatment with aqueous Tos-C ... 

Metalation and Reactivity with Electrophiles. The reaction of 2-(trimethylsilyl)thiazole (1) with carbon electrophiles such as aldehydes, ketones, ketenes, carboxylic acid chlorides, and azaaryl cations has attracted considerable attention. In this series, Nagasaki and coworkers reported the use of trimethylsilyl heteroarenes as the heteroarenyl carbanion donors in the electrophilic cyanation and described, for example, the electrophilic cyanation of 2-TST (1) with p-toluenesulfonyl cyanide in the absence of solvent (eq 25). ... 

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