Hydrogen Chloride In Acetic Acid Research Articles

An efficient synthesis of 5α-androst-1-ene-3,17-dione

5α-Androst-1-ene-3,17-dione ( 5) as a prodrug of 1-testosterone ( 4) was prepared in four steps from 17β-Acetoxy-5α-androstan-3-one (stanolone acetate) ( 1) in high yield. Thus, stanolone acetate ( 1) was brominated in the presence of hydrogen chloride in acetic acid to give 17β-acetoxy-2-bromo-5α-androstan-3-one ( 2), which underwent dehydrobromination using lithium carbonate as base with lithium bromide as an additive to give 17β-acetoxy-5α-androst-1-en-3-one ( 3) in almost quantitative yield with 97% of purity. Compound ( 3) was hydrolyzed with sodium hydroxide to give 17β-hydroxy-5α-androst-1-en-3-one (4,1-testosterone), which was oxidized with chromium trioxide to afford 5α-androst-1-ene-3,17-dione ( 5). The overall yield of 5 was 78.2% with purity of 99%. In this method, the formation of 4-ene was diminished when 1-ene was introduced, and its mechanism was also discussed.

Phosphonium Ylides Stabilized with Cyano Group and 5-Acylamino-4-phenyl-2-thiazolyl Residue

Available ylide reagent Ph3P = C(CN)C(S)NH2 readily enters cyclocondensation with N-(chlorophenacyl)benzamide and its analogs. By this route were prepared new stabilized phosphonium ylides containing cyano group and the corresponding 5-acylamino-4-phenyl-2-thiazolyl fragment. All these compounds even under standard conditions are dephosphorylated under the action of hydrogen chloride in acetic acid to form 5-acylamino-4-phenyl-2-cyanomethylthiazoles in high yields. Their structure was proved by spectroscopic studies and independent synthesis.

Rearrangement of 1-acetylindoxyl oxime to 1-acetyl-2-chloro-3-iminoindoline hydrochloride

Rearrangement of 1-acetylindoxyl oxime upon treatment with hydrogen chloride in acetic acid results in the formation of 1-acetyl-2-chloro-3-iminoindoline hydrochloride. Hydrolysis and acylation of the latter have been studied, along with reaction of 1-acetyl-2-chloro-3-(Ω-chloroacetyl)aminoindole with N- and S-nucleophiles.

Synthesis of 4-O-Acetyl-2,3-dideoxy-3-(tetrabromophthalimido)-D-threo-pentopyranosyl Chloride

4-O-Acetyl-2,3-dideoxy-3-tetrabromophthalimido-D-threo-pentopyranosyl chloride (4) was synthesized from the mixture 1-3 by treatment with hydrogen chloride in acetic acid. The structure is confirmed by reaction of 4 to give 4-O-acetyl-3-tetrabromophthalimido-1,2,3-trideoxy-D-threo-pent-1-eno-pyranose (5) and 4-O-acetyl-2,3-dideoxy-3-tetrabromophthalimido-1-[9-(6-phenylamino -2-methylpurinyl)]-ß-D-threo-pentopyranose (6).

SOLID PHASE SYNTHESIS OF PORCINE LH‐RELEASING HORMONE WITH HYDROGEN CHLORIDE IN FORMIC ACID AS THE DEBLOCKING REAGENT*

The decapeptide corresponding to the amino acid sequence of porcine luteinizing hormone-releasing hormone (LH-RH) which involves 1 mol of tryptophan was synthesized via solid phase synthesis with two different deblocking procedures which used hydrogen chloride in formic acid and hydrogen chloride in acetic acid containing 1% 2-mercaptoethanol. After some fundamental studies on the former reagent with respect to deblocking efficiency toward the Boc group, 0.5 M hydrogen chloride (a 10-fold molar excess with respect to the N-terminal Boc group) in formic acid was used in the present synthesis. The two synthetic products exhibited the same chemical and biological properties as an authentic LH-RH. Hydrogen chloride in formic acid has proved effective without a scavenger although loss of peptide from the resin occurred to a somewhat greater extent than that with hydrogen chloride in acetic acid. A derivative of the synthetic LH-RH formylated at the indole nitrogen had a greatly diminished biological activity, indicating that the intact indole side chain is essential for the activity.

ChemInform Abstract: REACTIONS OF BENZENESULFONOHYDRAZIDES AND BENZENESULFONAMIDES WITH HYDROGEN CHLORIDE OR HYDROGEN BROMIDE IN ACETIC ACID

AbstractDie Umsetzung der Benzolsulfonylhydrazide (I) mit trockenem Chlorwasserstoff oder Bromwasserstoff in Eisessig führt über eine Sulfinsäurezwischenstufe zu Thiosulfonaten und/oder Disulfiden (II) und (III).

Reactions of benzenesulfonohydrazides and benzenesulfonamides with hydrogen chloride or hydrogen bromide in acetic acid.

Benzenesulfonohydrazides capable of yielding a sulfinic acid intermediate by virtue of a basic nitrogen atom in the second position of the hydrazide moiety produced thiosulfonates when treated with 1 N hydrogen chloride in acetic acid and produced disulfides when treated with 1 N hydrogen bromide in the same solvent. In two cases, a crystalline mixture of P-nitrophenyl p-nitrobenzenethiosulfonate and bis(p-nitrophenyl) disulfide was isolated from the hydrogen chloride reactions. No reaction product was obtained from either the hydrogen chloride or hydrogen bromide reaction with benzenesulfonohydrazides that were unable to form a sulfinic acid intermediate. Reduction of benzenesulfonamides to disulfides appeared to be possible only with hydrogen bromide in acetic acid. No thiosulfonate was isolated from the treatments of benzenesulfonamides with 1 N hydrogen chloride in acetic acid. p-Nitrophenyl p-nitrobenzenethiosulfonate and p-bromophenyl p-bromobenzenethiosulfonate exhibited some antimicrobial activities against Gram-positive bacteria. The latter compound also showed analgesic properties in the phenylquinone test.

ChemInform Abstract: HYDRAZIDE AS A CARBOXYL PROTECTING GROUP, DEPROTECTION BY ACIDOLYSIS

AbstractDie Abspaltung der Hydrazidgruppe aus den L‐Aminosäurehydraziden (I) mit den Reagenzien a)‐d) unter Bildung der Säuren (II) wird untersucht.

Hydrazide as a Carboxyl Protecting Group deprotection by acidolysis

AbstractElimination of the hydrazide group was studied with the model compounds N‐benzoyl‐glycine hydrazide and N‐benzoyl‐L‐phenylalanine hydrazide, using phosphorus oxychloride, hydrogen bromide or hydrogen chloride in acetic acid, or 60% perchloric acid. It was found that treatment of N‐benzoyl‐L‐phenylalanine hydrazide with perchloric acid gave N‐benzoyl‐L‐phenylalanine in 100% yield and without racemisation.

ChemInform Abstract: REACTION OF ACETYLENES WITH HYDROGEN CHLORIDE IN ACETIC ACID, EFFECT OF STRUCTURE UPON ADE2 AND AD3 REACTIONS RATES

Chemischer InformationsdienstVolume 5, Issue 36 Isocyclic Compounds ChemInform Abstract: REACTION OF ACETYLENES WITH HYDROGEN CHLORIDE IN ACETIC ACID, EFFECT OF STRUCTURE UPON ADE2 AND AD3 REACTIONS RATES R. C. FAHEY, R. C. FAHEYSearch for more papers by this authorM. T. PAYNE, M. T. PAYNESearch for more papers by this authorD. J. LEE, D. J. LEESearch for more papers by this author R. C. FAHEY, R. C. FAHEYSearch for more papers by this authorM. T. PAYNE, M. T. PAYNESearch for more papers by this authorD. J. LEE, D. J. LEESearch for more papers by this author First published: September 10, 1974 https://doi.org/10.1002/chin.197436182AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume5, Issue36September 10, 1974 RelatedInformation

Reaction of acetylines with hydrogen chloride in acetic acid. Effect of structure upon AdR2 and Ad3 reaction rates

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTReaction of acetylines with hydrogen chloride in acetic acid. Effect of structure upon AdR2 and Ad3 reaction ratesRobert C. Fahey, Michael T. Payne, and Do-Jae LeeCite this: J. Org. Chem. 1974, 39, 8, 1124–1130Publication Date (Print):April 1, 1974Publication History Published online1 May 2002Published inissue 1 April 1974https://doi.org/10.1021/jo00922a024RIGHTS & PERMISSIONSArticle Views169Altmetric-Citations18LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (883 KB) Get e-Alerts Get e-Alerts

Improved Solid-Phase Synthesis of Tryptophan-Containing Peptides. II. Use of Nα-t-Butyloxycarbonyl-Ni-formyltryptophan

Abstract Ni-Formyltryptophan has proved to be more resistant than tryptophan against oxidation mediated by hydrogen chloride in acetic acid. Nα-t-Butyloxycarbonyl-Ni-formyltryptophan has been synthesized via nonaqueous acylation reaction and used for the solid-phase synthesis of tryptophan-containing peptides, in combination with hydrogen chloride in formic acid as the reagent for cleavage of the t-butyloxycarbonyl group. The validity of the method has been demonstrated, on the basis of several criteria, in the synthesis of the tryptophan-containing octapeptide, Lys–Gly–Val–Leu–Ala–Gly–Trp–Leu.

Deuterium exchange in alkylpyridines

In experiments designed to elucidate the stereochemical course of reduction occurring during the solvolysis of an alkylquinoline compound in formic acid, it was observed that all benzylic hydrogen atoms were completely exchanged by deuterium when the compound was heated in formic acid-d/sub 2/. While it is well known that benzylic hydrogen atoms in the 2- and/or 4-position of the pyridine (and related) ring systems undergo deuterium exchange readily in alkaline medium, there have been no previous reports of such exchange in organic acids. In initial studies it was observed that alkylpyridines do not undergo deuterium exchange in D/sub 2/O containing excess DC1. It was found, however, that exchange occurred readily at the 2- and 4-benzylic positions in alkylpyridines in deuterioacetic acid. Hydrogen chloride in acetic acid, in contrast to hydrogen chloride in water, did not prevent exchange. Exchange also took place, though quite slowly, in 2-alkylpyridines in boiling deuterium oxide. Experimental details are presented and results are discussed. (UK)

Kinetics and stereochemistry of the reaction of diethyl maleate and diethyl fumarate with hydrogen chloride in acetic acid

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTKinetics and stereochemistry of the reaction of diethyl maleate and diethyl fumarate with hydrogen chloride in acetic acidRobert C. Fahey and Hans Joerg SchneiderCite this: J. Am. Chem. Soc. 1970, 92, 23, 6885–6893Publication Date (Print):November 1, 1970Publication History Published online1 May 2002Published inissue 1 November 1970https://doi.org/10.1021/ja00726a027RIGHTS & PERMISSIONSArticle Views90Altmetric-Citations8LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (985 KB) Get e-Alerts Get e-Alerts

Homolytic mechanisms of aromatic rearrangements. Part I. The rearrangement of N-chloroacetanilide

The kinetics and products of the rearrangement of N-chloroacetanilide, catalysed by light and by benzoyl peroxide in carbon tetrachloride, catalysed by t-butyl peroxide in chlorobenzene, and in hot glacial acetic acid, and the products of the rearrangement catalysed by hydrogen chloride in acetic acid and in carbon tetrachloride, have been investigated. The reactions in the presence of light or free-radical initiators, and in acetic acid, are autocatalysed, partly owing to the formation of hydrogen chloride in a side-reaction. The kinetics, and the ratios of isomeric chloroacetanilides formed under various conditions, are consistent with an initial homolytic reaction, which is followed by a faster, heterolytic reaction, catalysed by hydrogen chloride. In the presence of organic peroxides, a third mechanism, involving nuclear chlorination of acetanilide by t-butyl hypochlorite or benzoyl hypochlorite, is also an important contributor to the total reaction.

Stereospezifische Synthese und Isomerisierung der 10‐Chlor‐decahydroisochinoline. Decahydroisochinoline. IV. Teil

AbstractTreatment of cis‐ and trans‐10‐hydroxy‐N‐methyl‐decahydroisoquinoline, (3a) and (10a) respectively, or N‐methyl‐Δ9,10‐octahydroisoquinoline (4 a) with hydrogen chloride in acetic acid affords the thermodynamically more stable trans‐isomer of 10‐chloro‐N‐methyl‐decahydroisoquinoline (1a). On the other hand ring closure of β‐(cyclohexen‐1‐yl)‐ethylamines 11a or 11b with aqueous formaldehyde in the presence of chloride ions leads to the 10‐cis‐chlorides 2a or 2b in a kinetically controlled reactions.