- Conversion of thiols into sulfonyl halogenides under aerobic and metal-free conditions
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An environmentally benign, metal-free synthesis of sulfonyl chlorides and bromides from thiols in the presence of ammonium nitrate, an aqueous solution of HCl and HBr and oxygen as a terminal oxidant was developed. The reactivity of various substituted thiophenols, benzylic-, aliphatic- and heteroaromatic thiols was examined. Ammonium nitrate served as a source of nitrogen oxides (NO/NO2), which are the crucial players in a redox-catalytic cycle. Sulfonyl chlorides and bromides were isolated without extraction and "filtered" over a short pad of silica gel; the use of solvents was greatly reduced in comparison with traditional isolation and purification. A "one-pot" protocol for the conversion of thiol into sulfonamide is also demonstrated. Scale-up experiments on the preparation of sulfonyl chloride and bromide are shown. A possible reaction pathway is discussed.
- Jereb, Marjan,Hribernik, Luka
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supporting information
p. 2286 - 2295
(2017/07/24)
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- Phenylenediamine urotensin-II receptor antagonists and CCR-9 antagonists
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The present invention relates to urotensin II receptor antagonists, CCR-9 antagonists, pharmaceutical compositions containing them and their use.
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- Preparation of 2-chloro-5-methyl-pyridine
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A process for the preparation of 2-chloro-5-methylpyridine of the formula STR1 which comprises reacting 3-methyl-pyridine-1-oxide of the formula STR2 with a chlorinating agent of the formula STR3 in which R1 represents alkyl, halogenoalkyl, cycloalkyl, optionally substituted aryl, NR2 R3 or OR4 in which R2 and R3 individually represent alkyl, cycloalkyl or aryl or together represent alkanediyl or oxaalkanediyl and R4 represents alkyl, cycloalkyl or optionally substituted aryl, in the presence of a basic organic nitrogen compound and in the presence of a diluent at a temperature between about -20° C. and +150° C.
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- Quinolinoxy phenylsulphonamides
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New phenylsulphonamide of the formula in which STR1 R1 represents a pyridyl, quinolyl or isoquinolyl radical which is unsubstituted or substituted by halogen, alkyl, cycloalkyl, alkoxy, cyano, nitro, halogenoalkyl, halogenoalkoxy, alkoxycarbonyl or alkylsulphonyl, R2 represents hydrogen, cyano, nitro, halogen, alkyl, alkoxy, halogenoalkyl, halogenoalkoxy or alkoxycarbonyl, R3 represents an aryl radical which is unsubstituted or monosubstituted, disubstituted or trisubstituted by halogen, halogenoalkyl, halogenoalkoxy, alkyl, alkoxy, alkylthio, alkylsulphonyl, cyano, nitro or alkoxycarbonyl, the substituents being identical or different, or represents pentafluorophenyl or represents a straight-chain, branched or cyclic alkyl which is unsubstituted or substituted by halogen, aryl, aryloxy, cyano, alkoxycarbonyl, alkoxy, alkylthio or trifluoromethyl, and X represents an --O--, --A--B-- or --B--A-- group where A denotes --O--, STR2 and B denotes --CH2 -- or STR3 where R1 does not represent a pyridyl radical when x represents an --O-- group, and salts thereof are prepared by reacting appropriate amines with sulphonyl halides. The substituted phenylsulphonamides can be employed as active compounds for inhibiting enzymatic reactions and for inhibiting thrombocyte aggregations.
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- Process for preparing amides by reaction in presence of molecular sieve
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There is provided a process for preparing amides which comprises reacting an amine, or an amide, and an acid halide, or anhydride, in suitable molecular proportions, in an inert organic diluent, in the presence of an effective amount of a molecular sieve, until the reaction is completed, separating the molecular sieve, and recovering the amide from the organic mother liquor.
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