scholarly journals Asymmetric Reduction of Schiff’s Bases with Lithium Aluminium Hydride–Monosaccharide Complexes to Give Optically Active Secondary Amines

1984 ◽  
Vol 57 (6) ◽  
pp. 1658-1661 ◽  
Author(s):  
Stephen R. Landor ◽  
Olatunji O. Sonola ◽  
Austin R. Tatchell
Keyword(s):  
Asymmetric Reduction ◽  
Optically Active ◽  
Secondary Amines ◽  
Lithium Aluminium Hydride ◽  
Schiff’S Bases ◽  
Lithium Aluminium ◽  
Schiff's Bases

Asymmetric reduction of p-alkylacetophenones

1986 ◽  
Vol 51 (3) ◽  
pp. 684-686 ◽  
Author(s):  
Otakar Červinka ◽  
Anna Fábryová ◽  
Ivana Brožová ◽  
Miroslav Holík
Keyword(s):  
Asymmetric Reduction ◽  
Optically Active ◽  
Lithium Aluminium Hydride ◽  
Lithium Aluminium

Asymmetric reduction of p-alkylacetophenones Ia-VIIa with lithium aluminium hydride in the presence of (-)-quinine affords optically active alcohols Ib-VIIb of the (R)-(+) configuration in optical yields of about 50%.

N-substituted aminomethyl 4-cyclopentylphenyl ketones and 2-amino-1-(4-cyclopentylphenyl)ethanol: Synthesis and pharmacological screening

1983 ◽  
Vol 48 (2) ◽  
pp. 642-648 ◽  
Author(s):  
Zdeněk Vejdělek ◽  
Miroslav Protiva
Keyword(s):  
Secondary Amines ◽  
Lithium Aluminium Hydride ◽  
Substitution Reactions ◽  
Rotarod Test ◽  
Lithium Aluminium ◽  
Spontaneous Motility ◽  
Pharmacological Screening ◽  
Higher Doses ◽  
Hydroxyethyl Piperazine ◽  
Ethanol Synthesis

The non-characterized bromo derivative Ia, obtained by bromination of 4-cyclopentylacetophenone, afforded by substitution reactions with diethylamine, benzylmethylamine, benzylisopropylamine, piperidine, morpholine, 1-methylpiperazine and 1-(2-hydroxyethyl)piperazine the amino ketones IIa-VIIIa which were reduced with lithium aluminium hydride to the aminoalcohols IIb-VIIIb. Compounds IIIb and IVb were debenzylated by catalytic hydrogenation on palladium to the secondary amines IXb and Xb. The compounds prepared have central stimulant effects in higher doses which appears also in the rotarod test and in the evaluation of spontaneous motility. They have mostly a mild spasmolytic effect of the anticholinergic type, some of them bring about local anesthetic and diuretic effects. The adrenolytic and hypotensive effects were found only with single compounds.

Preparation of secondary alcohols of high optical purity

1986 ◽  
Vol 51 (2) ◽  
pp. 401-403 ◽  
Author(s):  
Otakar Červinka ◽  
Anna Fábryová ◽  
Irina Sablukova
Keyword(s):  
Nmr Spectroscopy ◽  
Optical Purity ◽  
Optically Active ◽  
Secondary Alcohols ◽  
Lithium Aluminium Hydride ◽  
Enantioselective Reduction ◽  
H Nmr ◽  
Lithium Aluminium ◽  
High Optical Purity ◽  
Optically Pure

Partially resolved enantiomers of optically active alcohols I-V, obtained by enantioselective reduction of the corresponding ketones with lithium aluminium hydride in the presence of (-)-quinine, were converted into crystalline 3,5-dinitrobenzoates or phenylcarbamates. The esters of the nearly optically pure enantiomers were separated by crystallization from the generally more soluble esters of the racemates. Optical purity of the hydrolytically liberated alcohols was determined by 1H NMR spectroscopy in the presence of chiral shifting agents.

Potential antidepressants: 1-(2-(Methoxy- and hydroxyphenylthio)phenyl)-2-propylamines

1990 ◽  
Vol 55 (4) ◽  
pp. 1077-1098 ◽  
Author(s):  
Jiří Urban ◽  
Zdeněk Šedivý ◽  
Jiří Holubek ◽  
Emil Svátek ◽  
Miroslav Ryska ◽  
...  
Keyword(s):  
Ethyl Formate ◽  
Secondary Amines ◽  
Primary Amines ◽  
Alternative Route ◽  
Lithium Aluminium Hydride ◽  
Tertiary Amines ◽  
Lithium Aluminium ◽  
Boron Tribromide ◽  
Pharmacological Testing ◽  
By Products

2-(Methoxyphenylthio)benzaldehydes Xa-Xd were reacted with nitroethane in boiling acetic acid to give the corresponding 1-aryl-2-nitropropenes XIIa-XIId; benzonitriles XIIIa and XIIIc and benzaldoximes XXIc and XXId were isolated as by-products. Chromatographed compounds XIIa-XIId were reduced with lithium aluminium hydride to the primary amines VIIa-VIId, and formylated by heating with ethyl formate to the formamides XIVa, XIVc, and XIVd. Reduction of the formamides with lithium aluminium hydride afforded the secondary amines VIIIa, VIIIc, and VIIId, and methylation of the primary amines with formic acid and formaldehyde gave the tertiary amines IXa, IXc, and IXd. Compound VIIIa was prepared also by an alternative route starting from the nitrile XIIIa and proceeding via XIXa and XIVa. Some of the methoxylated amines were demethylated either by heating with pyridine hydrochloride or by treatment with boron tribromide to the title compounds IVa, IVc, Vc, Vd, VIa, and VIc. The amines prepared were transformed to salts for characterization and for pharmacological testing. Compound VIIIa (hydrogen oxalate V⁄FB-15 475) showed clearly the character of a potential antidepressant.

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