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.

Organic sulfur compounds. VII. Some reactions of benzothiazine hydroxamic acids

1970 ◽  
Vol 48 (23) ◽  
pp. 3727-3732 ◽  
Author(s):  
R. T. Coutts ◽  
Sharon J. Matthias ◽  
E. Mah ◽  
N. J. Pound
Keyword(s):  
Acetic Acid ◽  
Hydrochloric Acid ◽  
Sodium Hydroxide ◽  
Unsaturated Acid ◽  
Hydroxamic Acids ◽  
Sulfur Compounds ◽  
The Other ◽  
Complex Reaction ◽  
Organic Sulfur Compounds ◽  
Derivatives Of

Treatment of (3,4-dihydro-4-hydroxy-3-oxo-2H-1,4-benzothiazin-2-yl)acetic acid (1a) with sodium hydroxide yields the corresponding lactam, i.e. (3,4-dihydro-3-oxo-2H-1,4-benzothiazin-2-yl)acetic acid, together with the α,β-unsaturated acid, 3,4-dihydro-3-oxo-2H-1,4-benzothiazine-Δ2,α-acetic acid. The 6-methyl- and 6-bromo-derivatives of 1a behaved similarly when reacted with sodium hydroxide but when 3,4-dihydro-4-hydroxy-3-oxo-2H-1,4-benzothiazine was so treated a more complex reaction occurred.Methyl (6-bromo-3,4-dihydro-4-hydroxy-3-oxo-2H-1,4-benzothiazin-2-yl)acetate was also treated with hydrochloric acid. The two products isolated were (6-bromo-3,4-dihydro-3-oxo-2H-1,4-benzothiazin-2-yl)acetic acid and (6-bromo-7-chloro-3,4-dihydro-3-oxo-2H-1,4-benzothiazin-2-yl)acetic acid.The action of hydrochloric acid on 3,4-dihydro-4-hydroxy-7-methyl-3-oxo-2H-1,4-benzothiazine also gave two products. One was the corresponding lactam; the other was unexpected and has been tentatively identified as bis[2-(3,4-dihydro-7-methyl-3-oxo-2H-1,4-benzothiazine].

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: 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).

Reduction of 3‐Acyl Derivatives of Oxindoles, Benzo[b]furan‐2‐ones, and Benzo[b]thiophen‐2‐ones to the Corresponding Alkyl Derivatives by Sodium Borohydride–Acetic Acid

2006 ◽  
Vol 36 (6) ◽  
pp. 765-769 ◽  
Author(s):  
Francis X. Smith ◽  
Brian D. Williams ◽  
Eric Gelsleichter ◽  
Judy A. Podcasy ◽  
John T. Sisko ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Sodium Borohydride ◽  
Alkyl Derivatives ◽  
Derivatives Of ◽  
Acyl Derivatives

8-Substitution derivatives of D-6-methylergoline-I

1983 ◽  
Vol 48 (1) ◽  
pp. 312-318 ◽  
Author(s):  
Jiří Křepelka ◽  
Drahuše Vlčková ◽  
Jiří Holubek ◽  
Jiří Roubík
Keyword(s):  
Acetic Acid ◽  
Sodium Borohydride ◽  
Dimethyl Sulphoxide ◽  
Quinoxaline Derivative ◽  
Derivatives Of ◽  
Dihydroxy Derivative

Reactions of esters I and II with methylsulphinylmethylsodium in dimethyl sulphoxide afforded β-keto sulphoxides III and IV, which were converted either into compounds V and VI under the conditions of the Pummerer rearrangement, or into ketones VII and VIII by the action of aluminium amalgam in 1,2-dimethoxyethane. Reduction of the compounds III and V with sodium borohydride produced β-hydroxy sulphoxide IX and dihydroxy derivative X respectively; the latter was characterised in the form of derivatives XI and XII. Condensation of the compound III with 1,2-diaminobenzene in acetic acid gave quinoxaline derivative XIII. The compounds prepared had no marked antilactation or antinidation activity.

Derivatives of 2-pyrazolin-5-one. V. Preparation and properties of 1′,2′-dihydrospiro[[2]pyrazoline-4,3′ (4′H)-quinoline]-5-one.derivatives and related compounds

1977 ◽  
Vol 55 (15) ◽  
pp. 2856-2866 ◽  
Author(s):  
Ronald T. Coutts ◽  
Abdel-Monaem El-Hawari
Keyword(s):  
Acetic Acid ◽  
Sodium Borohydride ◽  
Lithium Aluminum Hydride ◽  
Catalytic Reduction ◽  
Aluminum Hydride ◽  
Spiro Compounds ◽  
Lithium Aluminum ◽  
Aldehydes And Ketones ◽  
Derivatives Of ◽  
Related Compounds

1′,2′-Dihydro-3-methyl-1-phenylspiro[[2]pyrazoline-4,3′(4′H)-quinoline]-5-one (8q), the structurally related 1,3-diphenylspiro[pyrazolone-quinoline] 8r and numerous 2′-substituted derivatives of 8q and 8r are readily accessible from catalytic reduction of 3-methyl-1-phenyl- or 1,3-diphenyl-4-(2-nitrobenzyl)-2-pyrazolin-5-one (1a, 1b, respectively) in alcohols (with the incorporation of the alkylidene moiety) or by interaction of the corresponding 2-aminobenzyl precursors (3a, 3b) with appropriate aldehydes and ketones. All spiro compounds were characterized by mass, ir, and 1Hmr spectra. The products obtained by reducing the spiro compounds with sodium borohydride and with lithium aluminum hydride are described. Reduction of 1a and 1b with zinc and acetic acid gave 3-methyl-1-phenyl- and 1,3-diphenyl-1H-pyrazolo[3,4-b]quinoline (2a, 2b, respectively).

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.

Sign in / Sign up

Export Citation Format

Share Document