Synthesis of new dibenzo[b,e]thiepin derivatives related to the antidepressant agent prothiadene

1979 ◽  
Vol 44 (8) ◽  
pp. 2536-2549 ◽  
Author(s):  
Miroslav Rajšner ◽  
Václav Bártl ◽  
Karel Šindelář ◽  
Emil Svátek ◽  
Jiří Holubek ◽  
...  
Keyword(s):  
Carboxylic Acid ◽  
Acrylic Acid ◽  
Primary Amine ◽  
Hydrobromic Acid ◽  
Main Product ◽  
Hydrogen Bromide ◽  
Geometric Isomers ◽  
Bromo Derivative ◽  
Antidepressant Agent ◽  
Boron Tribromide

A reaction of dibenzo[b,e]thiepin-11(6H)-one with cyclopropylmagnesium bromide afforded the carbinol VII giving by treatment with hydrogen bromide the bromo derivative IV. Application of the Gabriel synthesis led to the primary amine III postulated earlier to be a metabolite of the antidepressant agent prothiadene (I). Demethylation of 2-methoxy-11-(3-dimethylaminopropylidene)-6,11-dihydrodibenzo[b,e]thiepin (X) with boron tribromide or hydrobromic acid gave mixtures of geometric isomers of the phenol IX from which either the trans- or cis-form could be isolated; trans-IX is another potential metabolite of prothiadene (I). Attempts at preparing prothiadene N-oxide yielded as the main product the nitrogen-free diene XI which was apparently formed by a Cope elimination. The analogous sulfone XII was obtained as a by-product of the preparation of prothiadene S,S-dioxide (XV). Treatment of dibenzo[b,e]thiepin-11(6H)-one with methoxymethylmagnesium chloride opened the access to the aldehyde XVI which was further used for the preparation of the nitrile XVIII, alcohol XIX, carboxylic acid XX and acrylic acid XXI.

Cleavage of 3,3,4-trifluoro-2,2-dimethyloxetane by mineral acids

1985 ◽  
Vol 50 (9) ◽  
pp. 1948-1958 ◽  
Author(s):  
Václav Dědek ◽  
Ivan Veselý
Keyword(s):  
Aqueous Solution ◽  
Phosphoric Acid ◽  
Sulphuric Acid ◽  
Hydrobromic Acid ◽  
Polyphosphoric Acid ◽  
Acetyl Chloride ◽  
Main Product ◽  
Hydrogen Bromide ◽  
Mineral Acids ◽  
Sole Product

Cleavage of 3,3,4-trifluoro-2,2-dimethyloxetane (I) in an aqueous solution of sulphuric acid, phosphoric acid, hydrogen chloride, or hydrogen bromide gave a mixture of 2,2-difluoro-3-methyl-3-butenal (II) and 5,5-difluoro-2-(1,1-difluoro-2-hydroxy-2-methylpropyl)-4-hydroxy-6,6-dimethyl-1,3-dioxane (VIa); in the cleavage effected by hydrochloric or hydrobromic acid the mixture also contained 3-chloro- or 3-bromo-2,2-difluoro-3-methyl-1,1-butanediol (Vb or Vc). In alcoholic solutions of the mineral acids the cleavage afforded the corresponding acetals of butenal II and 2,2-difluoro-3-hydroxy-3-methylbutanal (IIIa). The action of sulphuric acid in the presence of acetyl chloride or acetanhydride led to 1-chloro-2,2-difluoro-3-methyl-3-butenyl acetate (IVd) or 2,2-difluoro-3-methyl-3-butenylidene diacetate (IVe), as the main product. Butenal II was a sole product of the cleavage of oxetane I by polyphosphoric acid at 150-160 °C in the gaseous phase. At temperatures above 180 °C there were also formed (in addition to butenal II) 1,1,5,5-tetrafluoro-2,6-dimethyl-1,6-heptadiene-4-ol (IX) and its formate (X).

Reactivity of Sodium Hexaethyl-2,4-dicarba-nido-hexaborate(1-)

1999 ◽  
Vol 64 (6) ◽  
pp. 977-985 ◽  
Author(s):  
Bernd Wrackmeyer ◽  
Hans-Jörg Schanz ◽  
Wolfgang Milius ◽  
Catherine McCammon
Keyword(s):  
Mössbauer Spectroscopy ◽  
Nmr Spectroscopy ◽  
Structural Analysis ◽  
Hydrogen Atom ◽  
Mossbauer Spectroscopy ◽  
Sandwich Complex ◽  
X Ray ◽  
Bromo Derivative ◽  
Boron Tribromide ◽  
C Nmr

Sodium hexaethyl-2,4-dicarba-nido-hexaborate(1-) (6), available from hexaethyl-2,4-dicarba- nido-hexaborane(8) (4) by deprotonation, reacts with deuterated methanol, CD3OD, to give back 4 without H/D exchange of the B-H-B hydrogen atom. The reaction of 6 with diethylboron chloride, Et2BCl, affords hexaethyl-2,4-dicarba-closo-hexaborane(6) (7), the first example of a peralkylated carborane of this type. In contrast, the reaction of 6 with boron tribromide, BBr3, leads mainly to 2,3,4,5,6,7-hexaethyl-2,4-dicarba-closo-heptaborane(7) (8), together with the corresponding 1-bromo derivative (9) and the closo-carborane 7 as side products. The reaction of two equivalents of 6 with FeCl2 gives the air-stable sandwich complex bis[hexaethyl-2,4-dicarba-nido-hexaborate(1-)]iron 10 which was characterised by X-ray structural analysis. All products were characterised by 1H, 11B and 13C NMR spectroscopy, and 57Fe Mössbauer spectroscopy was used to study 10.

Urobiliverdin, a New Bile Pigment Deriving from Uroporphyrin

1983 ◽  
Vol 38 (9-10) ◽  
pp. 753-757 ◽  
Author(s):  
Eva Benedikt ◽  
Hans-Peter Köst
Keyword(s):  
Carboxylic Acid ◽  
Main Product ◽  
Aminolevulinic Acid ◽  
Chromic Acid ◽  
Bile Pigment ◽  
Enzyme Extract ◽  
Crude Enzyme Extract ◽  
Chromatographic Behaviour ◽  
Vis Spectroscopy ◽  
Rhodopseudomonas Spheroides

5-Aminolevulinic acid is incubated with a crude enzyme extract from Rhodopseudomonas spheroides, mutant R 26. The formed porphyrins (main product: uroporphyrin III) are isolated. Incorporation of iron, ring-splitting by coupled oxydation and subsequent iron removal leads to a mixture of pigments, from which urobiliverdin, a new bile pigment with eight carboxylic acid side chains, is isolated. It is characterized by its chromatographic behaviour, chromic acid degra­dation and UV-vis spectroscopy.

scholarly journals Regioselective Base-induced Condensations of Acrylic Acid Derivatives

1999 ◽  
Vol 23 (3) ◽  
pp. 174-175
Author(s):  
E. Abdel-Ghani
Keyword(s):  
Carboxylic Acid ◽  
Acrylic Acid ◽  
Dicarboxylic Acid ◽  
Ethyl Acetoacetate ◽  
Tobacco Necrosis Virus ◽  
Necrosis Virus ◽  
Antiviral Activities

The orientation of cyclization of the reaction of methyl aroylacrylate (1) and aroylacrylic acid (8) with ethyl acetoacetate and/or thiourea leading to the formation of 4-aroylmethylcyclopentane-1,3-dione (2) 5-aryl-3-oxocyclohexene-1,2-dicarboxylic acid (9), 2-imino-5-aroylmethylthiazolidin-4-one (11) and 6-aryl-2-sulfonylpyrimidine-4-carboxylic acid (14) depends on the medium employed; some compounds show moderate antiviral activities against tobacco necrosis virus.

The synthesis of norbornanes with functionalized carbon substituents at a bridgehead. 1-(3-Oxonorborn-1-yl)ethanone and 1-(3-oxonorborn-1-yl)-2-propanone

1992 ◽  
Vol 70 (5) ◽  
pp. 1492-1505 ◽  
Author(s):  
Peter Yates ◽  
Magdy Kaldas
Keyword(s):  
Acetic Acid ◽  
Carboxylic Acid ◽  
Hydrogen Bromide ◽  
Tertiary Alcohol ◽  
Ethyl Bromoacetate ◽  
Second Molar ◽  
Molar Equivalent ◽  
Acid Lactone ◽  
Basic Hydrolysis ◽  
Hydrolysis Of

Treatment of 2-norobornene-1-carboxylic acid (7) with one equivalent of methyllithium in ether followed by a second molar equivalent after dilution with tetrahydrofuran gave 1-(norborn-2-en-lyl)ethanone (10) and only a trace of the tertiary alcohol 11. Reaction of 7 with formic acid followed by hydrolysis gave a 4:3 mixture of exo-3- and exo-2-hydroxynorbornane-1-carboxylic acid (16 and 17), whereas oxymercuration–demercuration gave only the exo-3-hydroxy isomer 16. Oxidation of 16 and 17 gave 3- and 2-oxonorbornane-1-carboxylic acid (27 and 29), respectively. Oxymercuration–demercuration of 10 gave exclusively 1-(exo-3-hydroxynorborn-1-yl)ethanone (30), which was also prepared by treatment of 16 with methyllithium in analogous fashion to that used for the conversion of 7 to 10. Oxidation of 30 gave 1-(3-oxonorborn-1-yl)ethanone (1). Dehydrobromination of exo-2-bromonorbornane-1-acetic acid and dehydration of 2-hydroxy-norbornane-2-acetic acid derivatives gave 1-(norborn-2-ylidene) acetic acid derivatives to the exclusion of norborn-2-ene-1 -acetic acid derivatives. Treatment of exo-5-acetyloxy-2-norobornanone (52) with ethyl bromoacetate and zinc gave ethyl exo-5-acetyloxy-2-hydroxynorbornane-(exo- and endo-2-acetate (53 and 54). Reaction of 53 with hydrogen bromide gave initially ethyl endo-3-acetyloxy-exo-6-bromonorbornane-1-acetate (59), which was subsequently converted to a mixture of 59 and its exo-3-acetyloxy epimer 61. Catalytic hydrogenation of this mixture gave a mixture of ethyl endo- and exo-3-acetyloxynorbornane-1 -acetate (62 and 63). Basic hydrolysis of this gave a mixture of the corresponding hydroxy acids, 70 and 71; the former was slowly converted to the latter at pH 5. Oxidation of the mixture of 70 and 71 gave 3-oxonorbornane-1-acetic acid (72). Treatment of the mixture with methyllithium as for 16 gave a mixture of 1-(endo- and exo-3-hydroxynorborn-1-yl)-2-propanone (73 and 74), which was oxidized to 1-(3-oxo-norborn-1-yl)-2-propanone (2). Reaction of exo-2-hydroxynorbornane-1-acetic acid lactone (75) with methyllithium in ether gave (1-(exo-2-hydroxynorborn-1-yl)-2-propanone (76), which on oxidation gave the 2-oxo isomer 78 of 2.

Preparation of Some 2-(Methoxyphenyl)-2H-benzotriazoles and the Corresponding Hydroxyphenyl Compounds

1987 ◽  
Vol 40 (10) ◽  
pp. 1663 ◽  
Author(s):  
J Rosevear ◽  
JFK Wilshire
Keyword(s):  
Acetic Acid ◽  
Good Yield ◽  
Hydrobromic Acid ◽  
Methoxy Group ◽  
Methylene Chloride ◽  
Thiourea Dioxide ◽  
Boron Tribromide

The reaction of several substituted o- nitronitrosobenzenes with O- and p- anisidine , and 2,4- dimethoxyaniline in acetic acid gives in good yield the corresponding enitroazobenzenes which are readily reduced with thiourea dioxide ( formamidinesulfinic acid) to the corresponding 2-(methoxypheny1)-2H-benzotriazoles, demethylation of which furnished the corresponding 2- (hydroxypheny1)-2H-benzotriazoles. Demethylation of the dimethoxy derivatives was best accomplished with boron tribromide in methylene chloride, the methoxy group located ortho to the benzotriazole ring being demethylated more readily than is the para-methoxy group. The reaction of enitroazobenzenes containing a methoxy group with hydrobromic acid in acetic acid results in cleavage of the azo bond and also partial bromination to give o- nitroaniline and some of its brominated derivatives.

α-CYANO-β-ARYLACRYLIC ACIDS

1945 ◽  
Vol 23b (2) ◽  
pp. 84-87 ◽  
Author(s):  
C. Y. Hopkins ◽  
Mary Chisholm ◽  
Ruth Michael
Keyword(s):  
Carboxylic Acid ◽  
Acrylic Acid

α-Cyano-β-arylacrylic acids have been prepared by condensing the following aldehydes with sodium cyanoacetate: 1-naphthaldehyde, 2,3-dimethoxybenzaldehyde, 3,4-diethoxybenzaldehyde, 6-chloropiperonal, 4-isopropylbenzaldehyde, 2-acetoxy-3-methoxybenzaldehyde, 2-hydroxy-3-methoxybenzaldehyde. The last-named gave α-cyano-β (2-hydroxy-3-methoxyphenyl) acrylic acid, which was readily converted to 8-methoxycoumarin-3-carboxylic acid.

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