Reduction by Dissolving Metals

1955 ◽  
Vol 8 (4) ◽  
pp. 512 ◽  
Author(s):  
AJ Birch ◽  
J Cymerman-Craig ◽  
M Slaytor
Keyword(s):  
Acid Hydrolysis ◽  
Good Yield ◽  
Liquid Ammonia ◽  
The Right

The reduction by sodium and ethanol, with or without liquid ammonia as solvent, of various amidines followed by acid hydrolysis, leads in many cases to a good yield of the corresponding aldehyde. Further reduction in liquid ammonia of several 2-aryl-imidazolines or imidazolidines followed by acid hydrolysis leads to the 2,5-dihydro-benzaldehyde derivative. The reduction of some acid amides by sodium and proton sources in liquid ammonia has been examined. Under the right conditions this process is of preparative value for aldehydes.

Hydroaromatic steroid hormones. IV. (+)-19-Nor-D-Homotestosterone

1955 ◽  
Vol 8 (4) ◽  
pp. 519 ◽  
Author(s):  
AJ Birch ◽  
RJ harrisson
Keyword(s):  
Acid Hydrolysis ◽  
Steroid Hormones ◽  
Methyl Ether ◽  
Liquid Ammonia

(+)-19-Nor-D-homotestosterone (III) has been synthesized by reduction of (+)-D-homo-oestrone methyl ether with lithium and ethanol in liquid ammonia, followed by acid hydrolysis.

4-O-METHYL-D-GLUCURONIC ACID AND 4-O-METHYL-D-GLUCOSE

1957 ◽  
Vol 35 (7) ◽  
pp. 595-598 ◽  
Author(s):  
P. A. J. Gorin
Keyword(s):  
Acid Hydrolysis ◽  
Good Yield ◽  
Glucuronic Acid ◽  
Hydrolysis Product ◽  
Novel Method

A novel method for the preparation of 4-O-methyl-D-glucuronic acid is described. This sugar and 4-O-methyl-D-glucose were obtained in good yield by two different series of reactions from 2-O-(4-O-methyl-D-glucopyranuronosido)-D-xylose, an acid hydrolysis product of the hemicellulose of Populustacamahacca Mill.

Preparation of Some 9-Hydroxy-2-oxaspiro[4.5]dec-8-ene-1,7-dione Derivatives by Reductive Alkylation of 3,5-Dimethoxybenzoic Acid With 1,2-Dihaloalkane and Oxiran Electrophiles

1989 ◽  
Vol 42 (8) ◽  
pp. 1207 ◽  
Author(s):  
JS Wilkie ◽  
KN Winzenberg
Keyword(s):  
Carboxylic Acid ◽  
Acid Hydrolysis ◽  
Liquid Ammonia ◽  
Major Product ◽  
Reductive Alkylation

Lithium in liquid ammonia mediated reductive alkylation of 3,5-dimethoxybenzoic acid (3) with 1,2-dibromoethane, or 1-bromo-2-chloroethane, followed by acid hydrolysis, afforded 9-hydroxy-2-oxaspiro[4.5]dec-8-ene-1,7-dione (1a). Reductive alkylation of (3) with unbranched 1,2-dibromoaikanes (5b-g), 1,2-dibromo-3-methylbutane and 1,2-dibromo-3,3-dimethylbutane gave 3-alkyl-9-hydroxy-2-oxaspiro[4.5]dec-8-ene-1,7-dione derivatives (1b-i) in moderate yields with the exception of (1i). The major product of the last reaction was 1-(2-bromo-3,3- dimethylbutyl )-3-hydroxy-5-oxocyclohex-3-ene-1-carboxylic acid (9). No reductive alkylation of (3) was observed with 2,3-dibromobutane or 1,2-dibromo-2methylpropane. Reductive alkylation of (3) with the oxiran derivatives (8a-d) afforded the 2-oxaspiro[4.5]dec-8-ene-1,7- dione derivatives (1a-c,j). Reductive alkylation of (3) with 1,3-dibromopropane and l-bromo-3-chloropropane gave, after hydrolysis, 1-(3-bromopropyl)-3-hydroxy-5-oxocyclohex-3-ene-l- carboxylic acid (12a) and 1-(3-chloropropyl)-3-hydroxy-5-oxocyclohex-3-ene-1-carboxylic acid (12b). The conversion of (1a) into 8-[1-( ethoxyimino )butyl]-9-hydroxy-2-oxaspiro[4.5]dec-8-ene-1,7-dione (2a) is described.

Preparation of aliphatic analogues of S-adenosyl-L-homocysteine and related compounds

1981 ◽  
Vol 46 (12) ◽  
pp. 3134-3144 ◽  
Author(s):  
Antonín Holý
Keyword(s):  
Hydrogen Sulfide ◽  
Acid Hydrolysis ◽  
Sodium Salt ◽  
Liquid Ammonia ◽  
Disodium Salt ◽  
Sodium Hydrogen ◽  
Benzylidene Derivative ◽  
Polymeric Compounds ◽  
Related Compounds

Reaction of 9-((RS)-2,3-dihydroxypropyl)adenine (I) with p-toluenesulfonyl chloride afforded the 3-O-p-toluenesulfonyl derivative II which on treatment with 2,3-dihydropyran was transformed into the 3-O-p-toluenesulfonyl-2-O-tetrahydropyranyl derivative III. Reaction of II with sodium isobutyl mercaptide in liquid ammonia gave 9-((RS)-3-isobutylthio-2-hydroxypropyl)adenine (IV). Analogously, compound III and disodium salt of L-homocysteine after acid hydrolysis afforded S-((RS)-3-(adenin-9-yl)-2-hydroxypropyl)-L-homocysteine (V). 9-((2S,3S)-threo-2,3-O-Isopropylidene-4-O-p-toluenesulfonyl-2,3,4-trihydroxybutyl)adenine (VIII) was transformed in a similar way into the 4-isobutylthio derivative IX and the L-homocysteine derivative X. 9-Allyladenine (XII) on treatment with bromine in dioxane afforded 9-((RS)-2,3-dibromopropyl)adenine (XIII) and probably 3,9-(2-bromotrimethylene)adeninium bromide (XIV). Reaction of compounds XIII, XIV and 9-((RS)-2,3-bis-p-toluenesulfonyloxypropyl)adenine (XI) with sodium hydrogen sulfide or sodium thioacetate led invariably to polymeric compounds. 4-p-Toluenesulfonyloxymethyl-2,2-dimethyl-1,3-dithiolane (XVa) reacted with sodium salt of adenine to give 9-(X)-2,2-dimethyl-1,3-dithiolane-4-ylmethyl)adenine (XVIa); analogously, 4-p-toluenesulfonyloxymethyl-2-phenyl-1,3-dithiolane (XVb) afforded the 2,3-S-benzylidene derivative XVIb and 1-p-toluenesulfonyloxy-2,3-bis(benzylthio)propane (XIXb) gave 9-((RS)-2,3-bis(benzylthio)propyl)adenine (XIXc). Acetolysis of XVIa or reduction of XVIb with sodium in liquid ammonia led to 9-((RS)-2,3-dimercaptopropyl)adenine (XVIII) and the corresponding episulfide XVII.

Organophosphorus compounds. V. Dialkyl alkylphosphonates from alkyl halides and sodium dialkyl phosphonates in liquid ammonia

1965 ◽  
Vol 18 (2) ◽  
pp. 163 ◽  
Author(s):  
A Meisters ◽  
JM Swan
Keyword(s):  
Carbon Tetrachloride ◽  
Good Yield ◽  
Benzyl Chloride ◽  
Liquid Ammonia ◽  
Organophosphorus Compounds ◽  
Alkyl Halides ◽  
Ethyl Bromide ◽  
Equivalent Quantity ◽  
Dialkyl Phosphonates

Liquid ammonia is a useful solvent for the reaction of various alkyl halides with sodium dialkyl phosphonates. In this medium ethyl bromide, amyl bromide, octyl bromide, ally1 chloride, and benzyl chloride give the corresponding dialkyl alkylphosphonates in good yield. In other cases, alternative products are formed. Thus sodium diethyl phosphonate reacts with carbon tetrachloride or chloroform in liquid ammonia to give diethyl phosphoramidate; dibromomethane gives diethyl methylphosphonate and an equivalent quantity of diethyl phosphoramidate. p-Nitrobenzyl bromide gives mainly 1,2-di(p-nitrophenyl)ethane, 1-bromooct-1-yne is reduced to oct-1-yne, and 3-bromoprop-1-yne gives mainly propyne together with some diethyl prop-l- ynylphosphonate.

The synthesis of 8-aza-3-deazaguanosine [6-amino-1-(β-D-ribofuranosyl)-υ-triazolo[4,5-c]pyridin-4-one] via a novel 1,3-dipolar cycloaddition reaction

1980 ◽  
Vol 58 (23) ◽  
pp. 2550-2561 ◽  
Author(s):  
Robert A. Earl ◽  
Leroy B. Townsend
Keyword(s):  
Spectral Data ◽  
Good Yield ◽  
Liquid Ammonia ◽  
Functional Group ◽  
Proton Nmr ◽  
Cycloaddition Reaction ◽  
Chemical Degradation ◽  
Dipolar Cycloaddition ◽  
Nuclear Overhauser Enhancement ◽  
Nuclear Overhauser

8-Aza-3-deazaguanosine (2) bas been prepared via a route which used a 1,3-dipolar cycloaddition reaction to provide a key intermediate. The reaction of 2′,3′,5′-tri-O-benzoyl-β-D-ribofuranosyl azide (13) with methyl 4-hydroxy-2-butynoate (11) provided a good yield of crystalline methyl 5-hydroxymethyl-1-(2,3,5-tri-O-benzoyl-β-D-ribofuranosyl)-υ-triazole-4-carboxylate (14). A series of functional group transformations were then used to convert 14 into methyl 5-cyanomethyl-1-(2,3,5-tri-O-benzoyl-β-D-ribofuranosyl)-υ-triazolo-4-carboxylate (19). Treatment of 19 with liquid ammonia effected not only a smooth removal of the blocking groups, but also an aminolysis of the ester function which was then followed by a ring annulation to provide 8-aza-3-deazaguanosine (2). The structures of these nucleosides were established on the basis of proton nmr spectral data and nuclear Overhauser enhancement data. The nucleosides obtained in this study were also converted through a chemical degradation sequence into nucleosides which had been obtained during an earlier work from our laboratory. The present study also provides unequivocal proof of the structures of some triazole nucleosides obtained in the earlier study.

An improved synthesis of 1,3-dihydro-1-methyl-5-phenyl-2H-pyrido[3,4-e]-1,4-diazepin-2-one via ortho-directed lithiation of 3-tert-butyl and 3-tert-butoxycarbonylaminopyridine

1987 ◽  
Vol 65 (6) ◽  
pp. 1158-1161 ◽  
Author(s):  
Charles Y. Fiakpui ◽  
Edward E. Knaus
Keyword(s):  
Acid Hydrolysis ◽  
Good Yield ◽  
Tert Butyl ◽  
Acid Catalyzed ◽  
Glycine Derivatives

The ortho-directed lithiation of 3-tert-butyl- or 3-tert-butoxycarbonylaminopyridines (3) with alkyllithiums and reaction with N,N-diethylbenzamide followed by acid hydrolysis gave 3-amino-4-benzoylpyridine (6) in good yield. Reaction of BTBO with the glycine derivatives 7a, b and then reaction with 6 afforded 3-alkoxycarbonylaminomethylcarbonylamino-4-benzoylpyridines 8a, b. Acid-catalyzed hydrolysis and cyclization of 8a, b yielded 9, which on methylation gave 1,3-dihydro-1-methyl-5-phenyl-2H-pyrido[3,4-e]-1,4-diazepin-2-one (10) in 36% overall yield from 3a.

BROMINATION OF STEROID 20-KETALS

1959 ◽  
Vol 37 (2) ◽  
pp. 345-350 ◽  
Author(s):  
Arthur A. Amos ◽  
P. Ziegler
Keyword(s):  
Methyl Ester ◽  
Acid Hydrolysis ◽  
Good Yield ◽  
Acid Methyl Ester ◽  
Acid Methyl ◽  
Hydrolysis Of

Bromination of 3α,12α-diacetoxypregnan-20-one ethylene ketal provided in good yield the corresponding 21-monobromo compound. This product, on acid hydrolysis and subsequent acetolysis, gave the known 3α,12α,21-triacetoxypregnan-20-one. Acid hydrolysis of the bromoketal, followed by Faworsky rearrangement, led to 3α,12α-diacetoxy-17α-methyletiocholanic acid methyl ester.

A MANNAN PRODUCED BY SACCHAROMYCES ROUXII

1956 ◽  
Vol 34 (12) ◽  
pp. 1796-1803 ◽  
Author(s):  
P. A. J. Gorin ◽  
A. S. Perlin
Keyword(s):  
Acid Hydrolysis ◽  
Good Yield ◽  
Structural Unit ◽  
Main Chain ◽  
Lead Tetraacetate ◽  
Side Chains

The main slime polysaccharide produced by Saccharomyccs rouxii during the fermentation of D-glucose to D-arabitol is a mannan. Acetolysis of the polymer has afforded di- and tri-saccharides in good yield, but no higher oligosaccharides were produced. The disaccharide is shown by methylation and lead tetraacetate oxidation to be 2-O-α-D-mannopyranosyl-D-mannose, establishing the presence of a 1,2-α-linkage in the polysaccharide. On acid hydrolysis the methylated mannan gives mainly 2,3,4,6-tetra-O-methyl-D-mannose, 3,4,6-tri-O-methyl-D-mannose, and 3,4-di-O-methyl-D-mannose; lesser components found are 2,4,6-tri-O-methyl-D-mannose and 3-O-methyl-D-mannose. The methylation and acetolysis data together suggest an average structural unit consisting of a main chain of D-mannopyranose units containing alternate 1,2- and 1,6-linkages, to which single D-mannopyranose units are attached by 1,2-linkages as side chains; alternatively, 1,2-disaccharide units are attached as side chains by 1,2-linkages to a 1,6-linked main chain.

Fischer Indole Synthesis with Selected 2,3-Dideoxy-D-glycero-aldopentose Derivatives. Conversion of D-Xylose to (2S)-3-(Indol-3-yl)propane-1,2-diol

1996 ◽  
Vol 61 (2) ◽  
pp. 298-304 ◽  
Author(s):  
Stevan Lajšic ◽  
Gordana Cetkovic ◽  
Mirjana Popsavin ◽  
Velimir Popsavin ◽  
Dušan Miljković
Keyword(s):  
Acid Hydrolysis ◽  
Raney Nickel ◽  
Good Yield ◽  
Dimethyl Acetal ◽  
Fischer Indole Synthesis ◽  
Fischer Indolization ◽  
Efficient Route ◽  
Indole Synthesis ◽  
Hydrolysis Of

Two independent routes towards (2S)-3-(indol-3-yl)propane-1,2-diol (11) were achieved starting from 3,5-di-O-acetyl-1,2-O-cyclohexylidene-α-D-xylofuranose (1). Ethanethiolysis of 1 afforded acyclic diethyl dithioacetal 2 which was further O-deacetylated to give 3. Selective benzoylation of 3 gave 5-O-benzoyl derivative 4. Treatment of 4 with N-bromosuccinimide in methanol gave methyl furanoside 5 which was further desulfurized over Raney nickel to afford 6. An acid hydrolysis of 6 gave hemiacetal 7 which upon treatment with phenylhydrazine, according to standard Fischer indolization procedure, yielded a mixture of chiral indoles 10. O-Debenzoylation of 10 gave the crystalline diol 11. A more efficient route towards the chiral indole 11 included the initial dethioacetalation of 2 into dimethyl acetal 8 which was further desulfurized over Raney nickel to give the corresponding 2,3-dideoxy derivative 9. Direct Fischer indolization of 9 with phenylhydrazine, followed by O-deacetylation of intermediate 12, afforded the expected indole 11 in good yield.

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