Sulphonyl Cyanides

Ethoxy-2-propylbuta-l,3-diene andp-toiyl sulphonyl cyanide read Lo give a erysLallihc produeL What is this product given its NMR spectra set 28 ... 

The regioselective radical addition of -toluene-sulphonyl cyanide to alkenes has been achieved photochemically Regioselective adducts have also been obtained on irradiation of Se-phenyl(selenothioperoxy)benzoate with terminal or cyclic alkenes. 

Primary aliphatic amines may be oxidized to nitriles [151]. A new catalyst of this reaction is cobalt oxide prepared from cobalt (II) sulphate and sodium hydroxide [155]. Benzylamine dissolved in boiling benzene containing the catalyst is converted to benzonitrile in 85% yield when oxygen is bubbled through the solution. Arylsulphonyl cyanides may be prepared [156] in good yields by oxidation of the thiocyanates with 3-chloroperbenzoic acid in hexane at 60°. An aliphatic thiocyanate gave a low yield of the sulphonyl cyanide. 

The carbon—sulphur bond is fractured in the reaction of p-toluene-sulphonyl cyanide with sodium ethanethiolate in ethanol. Other thiols, not thiolates, can also fracture the carbon—sulphur bond . ... 

Sulphonyl Cyanides.—Arylsulphonyl cyanides are more reactive than aroyl cyanides in cycloaddition reactions, because of delocalization of CN TT-charge density this is illustrated by their cycloaddition to 5,5-dimethoxy-tetrahalogeno-cyclopentadienes. Olefins give jS-cyano-sulphones under irradiation (254 nm), e.g. ArS02CH2 CH(CN) (CHa)3Me from hex-l-ene. ... 

However, the ethoxy group of l-ethoxy-2-propylbuta-l,3-diene is no longer present. Evidently the p-toluensulphonyl cyanide (2) undergoes [4+2] cycloaddition to l-ethoxy-2-propylbuta-l,3-diene (i). The resulting dihydropyridine 3 aromatises with 1,4-elimination of ethanol to form 2-p-tolyl-sulphonyl-5-propylpyridine (4). 

The Michael-type addition, a nucleophilic addition of an anion to the carbon-carbon double bond of an a,(3-unsaturated ketone, aldehyde, nitrile, nitro, sulphonyl, or carboxylic acid derivative, provides a powerful tool for carbon-carbon bond formation. The reaction is most successful with relatively nonbasic ( soft ) nucleophiles such as thiols, cyanide, primary and secondary amines, and P-dicarbonyl compounds. There is often a competition between direct attack on the carbonyl carbon (1,2-addition) and conjugate addition (1,4-addition) when the substrate is an a,(3-unsaturated carbonyl compound. 

Methyl Homodaphniphyllate.—Daphniphylline has been converted into methyl homodaphniphyllate (90). Treatment of daphnialcohol (96) with toluene-p-sulphonyl chloride in pyridine gave the tosylate (97). Treatment of (97) with ethanolic potassium cyanide afforded a mixture of the nitrile (98) and the amide (99). This mixture was hydrolyzed with aqueous HCl, and the resulting acid was esterified with methanolic HCl to afford (90). The authors proposed that methyl... 

This method is particularly suitable for the synthesis of a-ethylenic and aromatic acyl cyanides but it also provides a valuable method of preparing certain aliphatic acyl cyanides (Table 6.6). The reaction fails with acryloyl chloride, sulphonyl chlorides, ethyl chloroformate and oxalyl chloride. 

A sulphonyl analogue of the normal Reissert compound has been postulated as an intermediate for the reaction in which isoquinoline is converted to 4-chlo-ro-l-cyanoisoquinoline (or 1-cyanoquinoline, in the presence of potassium hydroxide) on reaction with sulphuiyl chloride and potassium cyanide in water at 0° [114]. The yield is poor. 

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