Fetizon's Reagent Research Articles

One-Pot Mechanochemical Synthesis of Mono- and Bis-Indolylquinones via Solvent-Free Multiple Bond-Forming Processes.

Bis-indolylquinones are fungal natural products endowed with interesting pharmacological properties. Most of the previously described methodologies in solution for the construction of the bis-indolylquinone framework show disadvantages associated with long reaction times and difficult, waste-generating purifications. A one-pot mechanochemical methodology for the synthesis of indolylquinones was developed, starting from indoles and dihaloquinones in the presence of FeCl3 or p-TsOH as catalysts and Fetizon's reagent as an oxidant. In contrast to solution chemistry, mechanochemical activation allowed the double addition of indole to a quinone substrate in one pot, leading to symmetrical or non-symmetrical bis-indolylquinones via a domino processes comprising up to six steps. In terms of sustainability, the method has several advantages over the solution protocol, including much shorter reaction times, no external heating, one-pot operation, and the absence of chromatography, leading to a drastically better performance in green metrics and demonstrating the application of several principles of green chemistry, in particular principles 2, 3, and 5.

Oxidation of alcohols to aldehydes and ketones: a guide to current common practice

Chromium-based Reagents.- Activated Dimethyl Sulfoxide.- Hypervalent Iodine Compounds.- Ruthenium-based Oxidations.- Oxidations Mediated by TEMPO and Related Stable Nitroxide Radicals (Anelli Oxidation).- Oxidations by Hydride Transfer from Metallic Alkoxide.- Fetizon's Reagent: Silver Carbonate on Celite (R).- Selective Oxidations of Allylic and Benzylic Alcohols in the Presence of Saturated Alcohols.- Selective Oxidations of Primary Alcohols in Presence of Secondary Alcohols.- Selective Oxidations of Secondary Alcohols in Presence of Primary Alcohols.

Lipase‐Catalyzed Esterification of a (.+‐.)‐2,3‐Di(arylmethyl)‐1,4‐butanediol and Its Application to the Synthesis of (S,S)‐(+)‐Hinokinin.

Abstract Racemic trans‐2,3‐di[(3,4‐methylenedioxy)benzyl]‐1,4‐butanediol (dihydrocubebin) 6 was enantioselectively esterified using lipases as catalysts with vinyl acetate. Optically active (S,S)‐1,4‐butanediol 6 obtained was selectively oxygenated with a Fetizon reagent, affording (S,S)‐(+)‐hinokinin 9 in a high yield.

Lipase‐Catalyzed Esterification of a (±)‐2,3‐Di(Arylmethyl)‐1,4‐butanediol and Its Application to the Synthesis of (S,S)‐(+)‐Hinokinin

Racemic trans‐2,3‐di[(3,4‐methylenedioxy)benzyl]‐1,4‐butanediol (dihydrocubebin) 6 was enantioselectively esterified using lipases as catalysts with vinyl acetate. Optically active (S,S)‐1,4‐butanediol 6 obtained was selectively oxygenated with a Fetizon reagent, affording (S,S)‐(+)‐hinokinin 9 in a high yield.

Synthetic Studies on the Kinamycin Family of Antibiotics: Synthesis of 2-(Diazobenzyl)-p-naphthoquinone, 1,7-Dideoxy-3-demethylprekinamycin, and 1-Deoxy-3-demethylprekinamycin.

2-(Diazobenzyl)-p-naphthoquinone was synthesized from 2-benzyl-1,4-dimethoxynaphthalene by cerric ammonium nitrate oxidation to 2-benzyl-p-naphthoquinone followed by diazo transfer with tosyl azide. 1,7-Dideoxy-3-demethylprekinamycin was prepared from 1,4-dimethoxynaphthalene by bromination, lithiation, and condensation with acetanthranil to give 2-(2'-N-acetaminobenzoyl)-1,4-dimethoxynaphthalene, which, following deacylation, was subjected to Pschorr cyclization to give 1,3,7-trihydro-O,O-dimethylkinafluorenone. This was then demethylated, subjected to hydrazinolysis, and then oxidized with Fetizon's reagent to complete the synthesis. 1-Deoxy-3-demethylprekinamycin was synthesized from 3-bromo-1,5-dimethoxy-4-naphthol by an identical route.

Sterols: Tritium-labeling and selective oxidations

Evidence is presented which shows that in the preparation of radiolabeled cholesterol and other Δ 5-sterols via the technique of tritium exchange-labeling of keto steroids and their subsequent conversion to sterol, 3H is introduced primarily into positions 2 and 6 ([2,2,4.6- 3H]-cholest-5-en-3β-ol) rather than exclusively at 2 and 4 as the literature claims. The stoppered-vial method using sodium methoxide versus column using basic alumina was the preferred method of labeling. It gave labeled keto steroids of reproducible specific activity indicative of the number of exchangeable protons. Because the initial oxidation step is critical to the preparation of 3H-sterols especially on the small scale, four common oxidants: pyridinium chlorochromate (Corey reagent), silver carbonate on Celite (Fetizon reagent), aluminum isopropoxide (modified Oppenhauer reagent) and chromic acid (Jones reagent) were compared using as starting materials, cholesterol, cholest-8-en-3β-ol, ergosterol, 24-methylenecholesterol, 24(25)-dihydrolanosterol, lanosterol, sitosterol and stigmasterol. The effectiveness of the oxidant was markedly influenced by the molecular features of the sterol.

ChemInform Abstract: OXIDATIVE CYCLIZATION USING FETIZON REAGENT

Chemischer InformationsdienstVolume 9, Issue 19 Preparative Organic Chemistry ChemInform Abstract: OXIDATIVE CYCLIZATION USING FETIZON REAGENT R. B. BADIGER, R. B. BADIGERSearch for more papers by this authorA. M. MEHTA, A. M. MEHTASearch for more papers by this authorG. K. TRIVEDI, G. K. TRIVEDISearch for more papers by this author R. B. BADIGER, R. B. BADIGERSearch for more papers by this authorA. M. MEHTA, A. M. MEHTASearch for more papers by this authorG. K. TRIVEDI, G. K. TRIVEDISearch for more papers by this author First published: May 9, 1978 https://doi.org/10.1002/chin.197819083Read the full textAboutPDF 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. Volume9, Issue19May 9, 1978 RelatedInformation

The oxidation of partially protected 2-acetamido-2-deoxypyranoses with silver carbonate on celite

Silver carbonate on Celite (the Fetizon reagent) was shown to be selective as an oxidizing agent, and convenient for the preparation of various aldonolactones. Whereas substituted aldoses having the 1-hydroxyl group free were readily converted into the corresponding lactones, partially protected 2-acetamido-2-deoxypyranoses having more than one free hydroxyl group were selectively oxidized at C-1. The oxidation was carrried out in boiling benzene or 1,4-dioxane. A series of partially protected 2-acetamido-2-deoxy-1,5-aldonolactones [2-acetamido-4,6- O-benzylidene-2-deoxy- D-mannono-1,5-lactone ( 13),2-acetamido-4,6- O-benzylidene-2-deoxy- D-glucono-1,5-lactone ( 15), 2-acetamido-2-deoxy-4,6- O-isopropylidene- D-glucono-1,5-lactone ( 18), 2-acetamido-2-deoxy-4,6- O-isopropylidene- D-mannono-1,5-lactone ( 20), 2-acetamido-2-deoxy-3,4-di- O-methyl- D-mannono-1,5-lactone ( 24), and 2-acetamido-2-deoxy-3,4-di- O-methyl- D-glucono-1,5-lactone ( 25)] was thus prepared; for these, the oxidation was accompanied by two side-reactions: ( a) an elimination (dehydration) that gave the unsaturated lactones [2-acetamido-4,6- O-benzylidene-2,3-dideoxy- D- erythro-hex-2-enono-1,5-lactone ( 12), 2-acetamido-2,3-dideoxy-4,6- O-isopropylidene- D- erythro-hex-2-enono-1,5-lactone ( 17), and 2-acetamido-2,3-dideoxy-4- O-methyl- D- erythro-hex-2-enono-1,5-lactone ( 23)], and ( b) partial gluco-to- manno epimerization occurring during the oxidation of 2-acetamido-4,6- O-benzylidene-2-deoxy- D-glucopyranose ( 14), 2-acetamido-2-deoxy-4,6- O-isopropylidene- D-glucopyranose ( 16), and 2-acetamido-2-deoxy-3,4-di- O-methyl- D-glucopyranose ( 22). The free unsaturated lactone, 2-acetamido-2,3-dideoxy- D- erythro-hex-2-enono-1,5-lactone ( 26), was obtained on hydrolysis of the isopropylidene group in lactone 17.

Fragmentation reactions catalysed by Fétizon's reagent (silver carbonate on Celite)

Fetizon's reagent (silver carbonate on Celite) quantitatively fragments steroidal 17-ethynyl alcohols and 17- and 20-cyanohydrins to the corresponding ketones at approximately the same rate as that at which it oxidizes the allylic 3β-hydroxy-4-ene to the enone.

Oxydation allylique sélective en chimie des sucres au moyen du réactif de Fétizon. Note de laboratoire

AbstractD‐glucal is selectively oxidised to the corresponding enone with a 60–80% yield by Fétizon's reagent (Ag2CO3‐celite).