Polyphosphoric acid catalyzed conversion of 3-(methoxyphenyl)propionic acids to derivatives of [3.3]metacyclophane-1,10-diones and 1-indanones

1993 ◽  
Vol 58 (3) ◽  
pp. 556-559 ◽  
Author(s):  
Juan Zhang ◽  
Russell L. Hertzler ◽  
Elizabeth M. Holt ◽  
Thayne Vickstrom ◽  
Edmund J. Eisenbraun
ChemInform ◽  
2010 ◽  
Vol 24 (32) ◽  
pp. no-no
Author(s):  
J. ZHANG ◽  
R. L. HERTZLER ◽  
E. M. HOLT ◽  
T. VICKSTROM ◽  
E. J. EISENBRAUN

1980 ◽  
Vol 45 (11) ◽  
pp. 3166-3181 ◽  
Author(s):  
Karel Šindelář ◽  
Jiří Jílek ◽  
Jiří Körbl ◽  
Fedir Jančik ◽  
Emil Svátek ◽  
...  

Cyclization of the acids IV-VII with sulfuric or polyphosphoric acid resulted in the thioxanthones VIIIa-d which were treated with 3-dimethylaminopropylmagnesium chloride and gave the amino alcohols Xa-d. Their acid catalyzed dehydrations afforded the methoxy derivatives of chlorprothixene IIIa-d, mostly in form of mixtures of geometric isomers. Whereas the results of attempts to demethylate these products with boron tribromide gave mostly unsatisfactory results, the demethylation with pyridine hydrochloride at 190-200 °C was successful; alcohols X were the most suitable starting materials. In this manner, the hydroxy derivatives of chloroprothixene IIa-d were obtained, mostly as pure geometric isomers. The configuration was assigned on the basis of their IR spectra. Z-Isomers are potential metabolites of the neuroleptic agent chlorprothixene (I). Compounds II and III are little toxic, have low central depressant activity and are inactive cataleptically.


1982 ◽  
Vol 47 (5) ◽  
pp. 1382-1391 ◽  
Author(s):  
Jiří Jílek ◽  
Josef Pomykáček ◽  
Jiřina Metyšová ◽  
Miroslav Protiva

Acids IIa-c were prepared by reactions of (4-fluoro-2-iodophenyl)acetic acid with 4-methoxythiophenol, 4-ethoxythiophenol and 4-(ethylthio)thiophenol and cyclized with polyphosphoric acid in boiling toluene to dibenzo[b,f]thiepin-10(11H)-ones IIIa-c. Reduction with sodium borohydride afforded the alcohols IVa-c which were treated with hydrogen chloride and gave the chloro derivatives Va-c. Substitution reactions with 1-methylpiperazine resulted in the title compounds Ia-c out of which the methoxy derivative Ia was transformed by demethylation with boron tribromide to the phenol Id. Compounds Ia-d are very potent neuroleptics exhibiting a clear prolongation of the central depressant and some prolongation of the cataleptic activity.


1986 ◽  
Vol 51 (12) ◽  
pp. 2786-2797
Author(s):  
František Grambal ◽  
Jan Lasovský

Kinetics of formation of 1,2,4-oxadiazoles from 24 substitution derivatives of O-benzoylbenzamidoxime have been studied in sulphuric acid and aqueous ethanol media. It has been found that this medium requires introduction of the Hammett H0 function instead of the pH scale beginning as low as from 0.1% solutions of mineral acids. Effects of the acid concentration, ionic strength, and temperature on the reaction rate and on the kinetic isotope effect have been followed. From these dependences and from polar effects of substituents it was concluded that along with the cyclization to 1,2,4-oxadiazoles there proceeds hydrolysis to benzamidoxime and benzoic acid. The reaction is thermodynamically controlled by the acid-base equilibrium of the O-benzylated benzamidoximes.


2020 ◽  
Vol 36 (05) ◽  
pp. 976-979
Author(s):  
Neeta Sinha

The derivatives of 3-ferrocenyl isocoumarin were synthesized by the condensation of substituted homothphalic anhydride with ferrocene using phosphoric acid or anhydrous aluminium chloride as cyclising agent. Substituted homophthalic acid did not condense with ferrocene so homophthalic acids were converted into their anhydride and then allowed to react with ferrocene in the presence of polyphosphoric acid or in the presence of anhydrous aluminium chloride using dichloromethane as the solvent to give 3-ferrocenyl isocoumarins. 7-Methoxy, 6-methyl, 5,7-dihydroxy, 6,7-dimethoxy and 5,7-dimethoxy derivatives of 3-ferrocenyl isocoumarin were synthesized. All the compounds were characterised by melting point determination, elemental and spectral analysis.


1987 ◽  
Vol 70 (1) ◽  
pp. 151-160 ◽  
Author(s):  
Samuel L MacKenzie

Abstract The N-heptafluoroburyryl isobutyl derivatives of proteic amino acids are well resolved by gas chromatography and form the basis of a convenient, rapid assay. The derivatives are prepared by acid-catalyzed esterification at 120°C for 20 min in 3N HCl-isobutanol followed by acylation with heptafluorobutyric anhydride at 150°C for 10 min. The reaction sequence is performed without any transfers or extractions and thus is compatible with microscale analysis. A complete proteic amino acid profile can be completed in less than 20 min by using a packed column or less than 10 min by using a capillary column in combination with an elevated oven temperature program rate. Physiological sample matrixes, which frequently contain a complex mixture of components, and thus require maximum resolution, can be assayed in less than 1 h using a program rate of 4°C/min. A capillary column is recommended for this application. Capillary column chromatography, in combination with a nitrogenspecific detector, is useful for identifying and assaying nonproteic amino acids in physiological sample matrixes. Frequently, a prior cleanup of the sample can be avoided.


1971 ◽  
Vol 49 (17) ◽  
pp. 2797-2802 ◽  
Author(s):  
D. E. Horning ◽  
G. Lacasse ◽  
J. M. Muchowski

The sulfuric acid catalyzed acylation of 2-methyl-5-nitroisocarbostyril with carboxylic acid anhydrides gave the corresponding 4-acylated derivatives 3, which underwent reductive cyclization to 2-substituted derivatives of 4-methyl-1,3,4,5-tetrahydropyrrolo[4.3.2.de]isoquinolin-5-one (4). Alkaline hydrolysis of the six-membered lactam in 4 was accompanied by a retro-Mannich reaction to produce 2-substituted indole-4-carboxylic acids in about 40 % overall yield from 3.


2003 ◽  
Vol 39 (7) ◽  
pp. 985-991 ◽  
Author(s):  
O. I. Yarovaya ◽  
D. V. Korchagina ◽  
O. V. Salomatina ◽  
M. P. Polovinka ◽  
V. A. Barkhash

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