Asymmetric syntheses. Part IX. Reduction of ketone oximes and their O-substituted derivatives with the lithium aluminium hydride–3-O-benzyl-1,2-O-cyclohexylidene-α-D-glucofuranose complex to give optically active amines

1974 ◽  
pp. 1902-1904 ◽  
Author(s):  
Stephen R. Landor ◽  
Oluntunji O. Sonola ◽  
Austin R. Tatchell
Keyword(s):  
Optically Active ◽  
Lithium Aluminium Hydride ◽  
Asymmetric Syntheses ◽  
Lithium Aluminium

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.

Studies of the optically active compounds of Anacardiaceae Exudates. IV. The structures of the rearrangement products from the long chain alicyclic ketoalocohol of Tigaso oil in Alkali

1958 ◽  
Vol 11 (4) ◽  
pp. 538
Author(s):  
JA Lamberton
Keyword(s):  
Methyl Ether ◽  
Active Compound ◽  
Monomethyl Ether ◽  
Optically Active ◽  
Side Chain ◽  
Lithium Aluminium Hydride ◽  
Active Compounds ◽  
Hydride Reduction ◽  
Lithium Aluminium ◽  
Long Chain

The structure IIIa previously proposed for the β-diketone with an unsaturated side chain, obtained by the action of alkali on the optically active compound of Tigaso oil, is confirmed by the formation of methyl stearyl ketone and resorcinol monomethyl ether in the pyrolysis of the methyl ether (IV). An anomalous lithium aluminium hydride reduction of the methyl ether (IV) and other reactions are discussed. Unsuccessful attempts have been made to synthesize the tribasic acid resulting from sodium hypobromite oxidation of the β-diketone (IIIb).

Chemistry of the Podocarpaceae. XXXVII. Oxidative degradations of phyllocladene and isophyllocladene : conversion of isophyllocladene into (+)-Podocarp-8(14)-en-13-one

1972 ◽  
Vol 25 (5) ◽  
pp. 959 ◽  
Author(s):  
RC Cambie ◽  
RC Hayward
Keyword(s):  
Chromium Trioxide ◽  
Optically Active ◽  
Oxidative Decarboxylation ◽  
Lithium Aluminium Hydride ◽  
Keto Acid ◽  
Hydride Reduction ◽  
Lithium Aluminium ◽  
Villiger Oxidation

The ozonolysis of phyllocladene (2) and isophyllocladene (12) has been carried out under a number of different conditions and the ozonide (34) of isophyllocladene has been isolated and characterized. Conversion of phyllocladene (2) into the diacid (20) has been accomplished by several routes from the norketone (3). Isophyllocladene (12) has been converted into (+)-podocarp-8(14)-en-13-one (1), an optically active relay which is useful in synthesis. The route involves ozonolysis of isophyllocladene, Baeyer-Villiger oxidation of the keto aldehyde (25), lithium aluminium hydride reduction of the ester (27), and chromium trioxide-pyridine oxidation of the resulting keto aldehyde (32) which gives the keto acid (30) in 26% overall yield. Oxidative decarboxylation then affords the enone (1) in 14% yield.

Synthesis of racemic and optically active erythro- and threo-9-(2,3,4-trihydroxybutyl)adenines and related compounds

1979 ◽  
Vol 44 (2) ◽  
pp. 593-612 ◽  
Author(s):  
Antonín Holý
Keyword(s):  
Sodium Borohydride ◽  
Sodium Salt ◽  
Sodium Periodate ◽  
Optically Active ◽  
Protecting Groups ◽  
Lithium Aluminium Hydride ◽  
Acidic Hydrolysis ◽  
Lithium Aluminium ◽  
Hydrolysis Of ◽  
Related Compounds

Reduction of diethyl 2,3-O-isopropylidene-DL-tartrate (II) with lithium aluminium hydride afforded 2,2-dimethyl-1,3-dioxolane-threo-4,5-dimethanol (III) which was transformed to the monotosyl derivative VI. Reaction of this compound with sodium salt of adenine, followed by acidic deblocking, gave 9-(DL)-threo-(2,3,4-trihydroxybutyl)adenine (IX). Analogously, 9-(DL)-erythro-(2,3,4-trihydroxybutyl)adenine (XVII) was prepared from diethyl meso-tartrate (XI) via the diol XIII and the tosyl derivative XV. 1,3-O-Benzylidene-D-threitol (D-XVIII) was converted successively into the 4-O-tosyl derivative XIX and the 2-O-benzoyl-4-O-tosyl derivative XX. Reaction of the compound XX with sodium salt of adenine, followed by removal of the protecting groups in the intermediate XXI, afforded 9-(D)-threo-(2,3,4-trihydroxybutyl)adenine (D-XXII); analogously, 1,3-O-benzylidene-L-threitol (L-XVIII) was transformed into the 9-(L)-threo-derivative L-XXII. The D-threo-derivative D-XXII was prepared also from 5-O-tosyl-3-O-benzoyl-1,2-O-isopropylidene-α-D-xylofuranoside (XXIII) or from 3-O-benzyl derivative XXIX by condensation with sodium salt of adenine, followed by acidic hydrolysis, degradation of the 1,2-diol grouping by sodium periodate and sodium borohydride, and methanolysis or hydrogenolysis. An analogous procedure was used for preparation of 1-(D)-threo-(2,3,4-trihydroxybutyl)uracil (D-XXVII). Methyl 2,3-O-isopropylidene-5-benzoyl-6-tosyl-D-mannofuranoside (XXXVI) was transformed to the 5-(adenin-9-yl) derivative XXXVII which after hydrolysis of the dioxolane ring, followed by cleavage of the cis-diol with sodium periodate, reduction with sodium borohydride and methanolysis, afforded 9-(D)-erythro-(2,3,4-trihydroxybutyl)adenine (D-XL). The L-enantiomer (L-XL) was obtained from 5-O-(adenin-9-yl)-3-O-benzoyl-1,2-O-isopropylidene-β-L-arabinofuranoside (XXXIIIb) by acidic cleavage, degradation of the intermediate XXXIV with periodate and methanolysis.

Sign in / Sign up

Export Citation Format

Share Document