ORGANIC SULFUR COMPOUNDS: PART I. BENZOTHIAZINE HYDROXAMIC ACIDS AND RELATED COMPOUNDS

1965 ◽  
Vol 43 (12) ◽  
pp. 3221-3231 ◽  
Author(s):  
R. T. Coutts ◽  
H. W. Peel ◽  
Elizabeth M. Smith
Keyword(s):  
Sodium Borohydride ◽  
Preparative Method ◽  
Hydroxamic Acids ◽  
Sulfur Compounds ◽  
Nucleophilic Attack ◽  
Organic Sulfur ◽  
Organic Sulfur Compounds ◽  
Azoxy Compound ◽  
Type V ◽  
Related Compounds

2H-1,4-Benzothiazine hydroxamic acids of type V (see Table I) are readily prepared by reducing suitably substituted (o-nitrophenylthio)acetates (II, R″ = Me or Et) by means of sodium borohydride and palladium–charcoal. The ester precursors can be prepared by the interaction of o-nitrothiophenols and α-bromoesters, but such a method is limited in scope. Diethyl bromomalonate, for example, reacts atypically with o-nitrothiophenol. The ester precursors are better prepared by Fischer–Speier esterification of the corresponding acids (II, R″ = H) which, in turn, are the products of nucleophilic attack by α-mercaptoacids on suitable o-chloro- (or bromo-) nitrobenzenes. This general preparative method failed in two instances. When o-chloronitrobenzene or 4-chloro-3-nitrotoluene was reacted with α-mercaptoisobutyric acid, the only acidic product obtained was α.,α′-dithiodiisobutyric acid.Reduction of methyl 2-(o-nitrophenylthio)benzoate (VI) with sodium borohydride and palladium–charcoal gave an azoxy compound, namely 2,2'-bis((o-methoxycarbonyl)phenylthio)azoxybenzene (VII).

Organic sulfur compounds. V. The preparation of some benzothiazine hydroxamic acids

1967 ◽  
Vol 45 (9) ◽  
pp. 975-981 ◽  
Author(s):  
R. T. Coutts ◽  
Elizabeth M. Smith
Keyword(s):  
Sodium Borohydride ◽  
General Structure ◽  
Hydroxamic Acids ◽  
Sulfur Compounds ◽  
Absolute Methanol ◽  
Aqueous Alcohol ◽  
Simple Ring ◽  
Organic Sulfur Compounds ◽  
Aryl Aldehydes ◽  
Related Compounds

2-Arylidene-3,4-dihydro-4-hydroxy-3-oxo-2H-1,4-benzothiazine hydroxamic acids (VI) were best prepared by the reduction of α-(o-nitrophenylthio)cinnamates and related compounds of general structure V with sodium borohydride and palladium–charcoal. These precursors (V) were obtained by reacting methyl (o-nitrophenylthio)acetate and its simple derivatives with a variety of aryl aldehydes, in the presence of piperidine. Attempts to prepare the sulfones of V in a similar manner from methyl or ethyl (o-nitrobenzenesulfonyl)acetate were successful in two instances when absolute methanol or ethanol was the solvent. The alternative reaction, in which one molecule of the aldehyde condensed with two molecules of the (o-nitrobenzenesulfonyl)acetate, also occurred.Methyl and ethyl (2-nitrobenzenesulfonyl)acetate and their simple ring-substituted derivatives were smoothly hydrolyzed and decarboxylated by heating a solution of the acetate in aqueous alcohol containing piperidine. Methyl p-nitrophenylsulfone is similarly obtained in an excellent yield from methyl (p-nitrobenzenesulfonyl)acetate. Neither methyl (o-nitrophenylthio) acetate nor methyl α-(4-trifluoromethyl-2-nitrobenzenesulfonyl)propionate is affected by this treatment.

Organic sulfur compounds. VI. Reduction of three α-(o-nitrophenylthio)ketones with sodium borohydride

1970 ◽  
Vol 48 (15) ◽  
pp. 2448-2452 ◽  
Author(s):  
R. T. Coutts ◽  
Sharon J. Matthias ◽  
H. W. Peel
Keyword(s):  
Benzyl Alcohol ◽  
Sodium Borohydride ◽  
Main Product ◽  
Sulfur Compounds ◽  
Organic Sulfur ◽  
Organic Sulfur Compounds ◽  
A Minor

Reduction of three α-(o-nitrophenylthio)ketones with sodium borohydride and palladium–charcoal gave mainly α-(o-nitrophenylthio)alcohols and, as minor products, α-(o-aminophenylthio)alcohols. Only two benzothiazines were formed. Bis[2-(3-phenyl-2H-1,4-benzothiazine)] was a minor product of the catalyzed reduction of ω-(o-nitrophenylthio)acetophenone whereas 1-(3,4-dihydro-4-hydroxy-3-oxo-2H-1,4-benzothiazin-2-yl)benzyl alcohol was the main product of the catalyzed reduction of α-benzoyl-α-(o-nitrophenylthio)acetate.

ORGANIC SULFUR COMPOUNDS: II. CATALYZED SODIUM BOROHYDRIDE REDUCTIONS OF SELECTED α-(o-NITROPHENYLTHIO) ACIDS

1966 ◽  
Vol 44 (15) ◽  
pp. 1733-1741 ◽  
Author(s):  
R. T. Coutts ◽  
D. L. Barton ◽  
Elizabeth M. Smith
Keyword(s):  
Acetic Acid ◽  
Reaction Temperature ◽  
Sodium Borohydride ◽  
Hydroxamic Acids ◽  
Isobutyric Acid ◽  
Sulfur Compounds ◽  
Reducing Agent ◽  
Organic Sulfur Compounds ◽  
Unexpected Product ◽  
Derivatives Of

The products obtained when α-(o-nitrophenylthio) acids are reduced by means of sodium borohydride and palladium–charcoal depend on (a) the reaction temperature, (b) the solvent, (c) the length of time in which the α-(o-nitrophenylthio) acid is in contact with the reducing agent, and (d) the nature of the substituents on the α-(o-nitrophenylthio) acid. By varying these conditions, benzothiazine hydroxamic acids (i.e. substituted 3,4-dihydro-4-hydroxy-3-oxo-2H-1,4-benzothiazines), the corresponding lactams (3,4-dihydro-3-oxo-2H-1,4-benzothiazines), and derivatives of 2-carboxymethylthioazobenzene can be prepared.In two cases, additional products were obtained. When (o-nitrophenylthio)acetic acid was catalytically reduced for 30 min in dioxane, 3,4-dihydro-3-oxo-2H-1,4-benzothiazine-1,1-dioxide (VIc) was an unexpected product, and when α-(4-trifluoromethyl-2-nitrophenylthio)-isobutyric acid was left for a prolonged time in contact with sodium borohydride and palladium–charcoal, a derivative of hydrazobenzene, namely, 2-carboxy(α,α-dimethyl)methylthio-5-trifluoromethylhydrazobenzene (V), was one of the three identified products.

scholarly journals Pollution status of volatile organic sulfur compounds causing odor in Xi River and factors influencing spatial distribution

2020 ◽  
Vol 20 (4) ◽  
pp. 1264-1270
Author(s):  
Xiang Tu ◽  
Shaohua Chen ◽  
Siyu Wang ◽  
Haiqing Liao ◽  
Xuejiao Deng
Keyword(s):  
Spatial Distribution ◽  
Sulfur Compounds ◽  
Organic Sulfur ◽  
Industrial Emissions ◽  
Diethyl Sulfide ◽  
Organic Sulfur Compounds ◽  
Factors Influencing ◽  
Pollution Status ◽  
Volatile Organic ◽  
Volatile Organic Sulfur Compounds

Abstract This study investigated the pollution status of volatile organic sulfur compounds (VOSCs) and the factors influencing their spatial distribution in the Xi River in Shenyang, China. A method for simultaneous determination of 14 VOSCs that cause odor in water samples was developed by using purge and trap coupled with gas chromatography and a flame photometric detector. The results indicated that each target compound could be identified from 15 sampling sites, and the total concentration of 14 VOSCs ranged from 2.575 to 52.981 μg L−1. Dimethyl sulfide (DMS) was the most important contaminant with an average concentration of 4.029 μg L−1, a detection rate of 93.33% and a variation coefficient of 0.72. The VOSCs were primarily distributed in suburban and rural sections, and the suburban section was the worst in regard to pollution by VOSCs. Dimethyl trisulfide was primarily distributed in urban and suburban sections of the Xi River due to industrial emissions. Ethanethiol, DMS, and ethyl methyl sulfide, which are typical by-products of microbial anaerobic decomposition from domestic wastewater, were found in abundance in the suburban section. Diethyl sulfide, diethyl disulfide, methyl propyl disulfide, and 1-propyl disulfide representing agricultural nonpoint source pollution were mostly distributed in the rural section.

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