Benzenesulfonyl isocyanate

To a solution of 10.2 g of 4-(p-(2-ethoxy-5-chlorobenzamido)ethyl)-benzenesulfonamide in 12.5 ml of 2 N sodium hydroxide solution and 30 ml acetone are added dropwise, at 0-5°C, 3.3 g of cyclohexyl isocyanate. The whole is stirred for 3 hours, diluted with water and methanol, undissolved matter is separeted by filtration. The filtrate is acidified with dilute hydrochloric acid. The 4-(p-(2-ethoxy-5-chlorobenzamido)ethyl)-benzenesulfonyl)-N -cyclohexylurea which precipitates in the form of crystals melts after recrystallization from methanol at 168-170°C. 

A 20 ml 50% solution of benzenesulfonyl isocyanate (0.10 mol) in toluene and 50 ml ethyl glyoxalate in toluene were refluxed 24 hours, then treated with 1,3-cyclohexadiene (0.21 mol), and refluxed an additional 10 hours. Upon cooling, a white precipitate was formed, which was recrystallized in EtOAc, and 19.1 g product isolated as a white solid. 

Acylation of benzotriazoles occurs in most instances on the 1- (or 3-)nitrogen atom. From 5-methylbenzotriazole and acetyl chloride or acetic anhydride, a mixture of l-acetyl-4-and -5-methylbenzotriazoles is obtained (13JCS1391). With acetic anhydride, benzoyl chloride or benzenesulfonyl chloride and 5,6-dimethylbenzotriazole, acylation on N-1 occurs (52JA4917) and no N-2 substitution product could be observed. Analogously, benzotriazole or 1-trimethylsilylbenzotriazole reacts with thiobenzoyl chloride to afford 1-thiobenzoyl-benzotriazole (73LA636). Similarly, with phenyl isocyanate 1-phenylcarbamoylbenzotriazole (143) is formed (49JA2297). 

Benzenesulfonic acid, 882 Benzenesulfonic anhydride, 46 Benzenesnlfonyl chloride, 46-48, 867, 1280 Benzenesulfonyl esters, 47 Benzenesnlfonyl isocyanate, 48 N-Benzenesulfonyl-1,4-naphthoquinone-4-imine, 559... 

Fig. 4.9 Synthesis scheme for the preparation of the fluorescent SAMs (DA, CA, TMA, DS, CS, TMS, DU, CU, and TMU) on glass and silicon surfaces, (i) Red Al, toluene, 45°C (ii) dansyl chloride, 7-dimethylaminocoumarin-4-acetic acid succinimidyl ester, or 5-(and-6)-carboxytetramethylrhodamine, succinimidyl ester, acetonitrile, rt (iii) benzenesulfonyl chloride orp-isopropylphenyl isocyanate, acetonitrile, rt. 36 Reproduced with permission of The Royal Society of Chemistry...

PHEMA has been effected. Reaction of p-nltro-benzenesulfonyl Isocyanate with PHEMA or copolymers containing HEMA and varying amounts of styrene followed by reduction of the nitro group with sodium dlthlonlte produced p-amlnobenzenesulfonyl carbamates of hydrogels (p-ABSC-HEMA). The precise composition of the hydrogel carbamates was determined by nonaqueous titration of the carbamate moiety with tetrabutylammonlum hydroxide In Isopropanol/dlmethylformamlde. 

Preparation of Hydrogel Arylsulfonyl Carbamates. To a solution of hydrogel (1-4.0 g) in dry pyridine (20-40 mL) was added eitherp-toluenesulfonyl Isocyanate (pTSI), 3.0 g, or p-nitro-benzenesulfonyl Isocyanate (p-NBSI), 0.5-3.0 g and the mixture was heated at 70 under nitrogen for 4 hr. The adduct was isolated by precipitation in benzene or ethanol. Repreclpltatlon from acetone or DMF yielded the desired products, IR (film) 3170 cm (-NH), 1530 cm" (-NO2), 1340, 1180 cm" (-SOj). The precise degree of substitution was determined by non-aqueous titration (Table II). 

OLEFIN ADDITIONS Benzenesulfonyl azide. Chlorosulfonyl isocyanate. Chiom-ous chloride. Cyanamlde. Dichloroketene. Dinitrogen tetroxide-Iodine. Diphenyl-ketene. Ethoxyketene. Fluoroxytrifluoro-methane. Iodine. Iodine azide. Iodine isocyanate. Iodobenzene dichloride. Mercuric azide. Nitrosyl chloride. Nitrosyl fluoride. Nitryl iodide. Potassium f-but-oxide-Bromoform (dibromocarbene). 

BENZENESULFONYL CHLORIDE (98-09-9) Combustible liquid (flash point 266°F/130°C). Contact with water, steam, or water solutions forms hydrochloric, chlorosulfonic, tmd benzenesulfonic acids. Aqueous solutions of this chemical are strong acids and react violently with bases. Violent reaction with strong oxidizers, dimethyl sulfoxide, and methyl formamide. Incompatible with ammonia, aliphatic amines, alkylene oxides, epichlorohydrin, isocyanates, water solutions. Attacks metals in the presence of moisture. 

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