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1- Methoxy-3-butanone

The most recent, and probably most elegant, process for the asymmetric synthesis of (+)-estrone appHes a tandem Claisen rearrangement and intramolecular ene-reaction (Eig. 23). StereochemicaHy pure (185) is synthesized from (2R)-l,2-0-isopropyhdene-3-butanone in an overall yield of 86% in four chemical steps. Heating a toluene solution of (185), enol ether (187), and 2,6-dimethylphenol to 180°C in a sealed tube for 60 h produces (190) in 76% yield after purification. Ozonolysis of (190) followed by base-catalyzed epimerization of the C8a-hydrogen to a C8P-hydrogen (again similar to conversion of (175) to (176)) produces (184) in 46% yield from (190). Aldehyde (184) was converted to 9,11-dehydroestrone methyl ether (177) as discussed above. The overall yield of 9,11-dehydroestrone methyl ether (177) was 17% in five steps from 6-methoxy-l-tetralone (186) and (185) (201). [Pg.436]

The comparison between the cycloaddition behavior of simple diazoketones and of ethyl diazopyruvate 56 towards the same olefin underlines the crucial influence of the ethoxycarbonyl group attached to the carbonyl function. This becomes once again evident when COOEt is replaced by an acetal function, such as in l-diazo-3,3-di-methoxy-2-butanone 86 with enol ethers and acetates, cyclopropanes rather than dihydrofurans are now obtained 113). ... [Pg.123]

Material accountability (the sum of recovered chloropinacolone, methyl pivaloyl acetate, and pinacolone) with the active Pd monophosphine and carbene complexes was in the range of 92-99% without accounting for impurities present in the starting chloropinacolone. A GC-MS examination of several product mixtures was undertaken to see if there were any additional, unanticipated by-products. The only additional material identified was a-methoxy pinacolone (l-methoxy-3,3-dimethyl-2-butanone). This compound was formed by methanolysis of the starting a-chloropinacolone and appears to be formed by a mixture of catalyzed and uncatalyzed processes Since this product was not anticipated, it was not quantified but represents the majority of, if not the only, remaining volatile product. No attempt was made to determine the presence of any quaternary ammonium salt formed by similar alkylation of the amine base by a-chloropinacolone. [Pg.389]

C(CH3)j CHj ch3 ch3 czh5 3-tert.- Butylamino-2,2-di-methoxy-butan 3-tert.-Butylamino-2,2-di-ethoxy-butan 81 33 3-tert. -Butylamino-2-butanon 65 ... [Pg.1148]

Exercise 16-28 Write equations to show how you would convert 2-butanone to 2-methoxy-2-methylthiobutane by way of the corresponding a-chloro ether. [Pg.704]

Adhesive (liquid, all purpose) acetone, methylacetate, ethylacetate, 8 2-butanone, 1 -ethoxy-1 -methoxy ethane, 1,1-diethoxyethane, 2,2-diethoxypropane, n-butylacetate... [Pg.353]

Exposure to VOCs in public beauty shops can also be high. Many cosmetic products contain VOCs such as 2-phenoxyethanol, 2-butanone, acetone, terpenes, 2-hydroxy-4-methoxy-benzophenone or phenylmethanol. In particular, hair sprays are potential sources of indoor pollutants. To estimate VOC concentrations associated with the use of beauty products, a female subject was placed in the model room described earlier and sprayed with 16.1 g hair lacquer. Propellant gases (butane, pentane), ethanol, limonene and tripropyleneglycol (isomers) were subsequently monitored in the room. Thirty minutes after the application of this product, the highest VOC concentrations were measured for ethanol (>100pg/m3)... [Pg.362]

In jS-chloroketones the C—Cl and C=0 groups show significant interaction, if the two entities are in the correct orientation with respect to each other136. This interaction results in an appreciable cr component in the LUMO of the / -chloroketone, and makes the C—Cl bond potentially photolabile in the excited state12,136. Indeed, irradiation of 4-chloro-2-butanone in methanol has been reported to afford the corresponding 4-methoxy ether in addition to the alcohol resulting from carbonyl reduction. The apparent nucleophilic photosubstitution product, however, turns out to be produced in a dark reaction, catalysed by acid which is formed when methanol solutions are irradiated255. [Pg.887]

Scheme 13.2 Synthesis of nabumetone (4-(6-methoxy-2-naphthenyl)-2-butanone. Scheme 13.2 Synthesis of nabumetone (4-(6-methoxy-2-naphthenyl)-2-butanone.
This is an addition-elimination reaction of methyllithium with iV-methyl-iV-methoxypropionamide forming 2-butanone. As illustrated below using arrow pushing, methyllithium initially adds to the amide. Unlike the process illustrated in Problem 6(f), a second methyllithium does not add and an alcohol is not formed. This is explained by the ability of lithium to coordinate between the two present oxygen atoms. The first is the oxygen of the former carbonyl and the second is the oxygen associated with the methoxy component of the illustrated amide. Due to the stability of this type of five-membered interaction, initial... [Pg.254]

Deprotection of MEM and MOM ethers. Methoxyethoxymethyl and methoxy-methyl ethers are cleaved to the alcohol by this reagent in high yields. Either 2-butanone or 2-methyl-2-propanol is recommended as solvent. The procedure is particularly useful for cleavage of ethers of allylic alcohols, for which ZnBr, and TiCh are not useful. [Pg.420]

SYNS ANISYLACETONE 2-BUTANONE, 4-(p-METHOXYPHENYL)-(6CI,7CI,8CI) ENT 20,279 FEMA No, 2672 4-METHOXYBENZYLACETONE p-METHOXYPHENYLBUTANONE 4-(p-METHOXY-PHENYL)-2-BUTANONE RASPBERRY KETONE METHYL ETHER... [Pg.892]

SYNS 2-BUTANONE, 4-(4-HYDROXY-3-xMETHOXY-PHENYL)- GINGERONE 4-(4-HYDROXY-3-METHOXYPHENYL)-2-BUTANONE (4-HYDROXY-3-METHOXYPHENYL)ETHYL METHYL KETONE 3-METHOXY-4-HYDROXY-BENZYLACETONE (0)-PARADOL ZINGERONE ZINGIBERONE... [Pg.1420]

Nabumetone. Nabumetone. 4-(6-mcthoxy-2-naphthyl)-2-butanone (Relafen), serves os a pmdnig to its aetive metabolite. 6-methoxy-2-naphthylacetic acid. Like the other aryla-cetic acid drugs, it is used in short- ur long-term management of RA and OA. It is available as tablets (500 and 750 mg), with a recommended. single daily dose of 1.000 mg. [Pg.759]

Write the strucmral formulas for the following (a) 2-methylbutanal (b) propanal (c) o-methoxy-benzaldehyde (d) butanone (e) bromopropanone (f) 3-heptanone. [Pg.1101]

Using a developed method, laser irradiation of colloidal mixtures of the three metals, these authors dispersed Au/Ag/Pd nanoparticles with average diameters 4.4 1.5 nm. These tri-metallic nanoparticles were assessed for activity in the synthesis of nabumetone [4-(6-methoxy-2-naphthalenyl)-2-butanone], a non-steroidal anti-inflammatory drug that has greater activity than aspirin and is comparable to naproxen and indomethacin. The 0.45-mol% Au/Ag/Pd was sufficient to catalyse the coupling of the 3-buten-2-ol... [Pg.449]

Wahrend 3-Methyl-3-(4-methoxy-phenyl)-butanon-(2)-azin fiber Platin(IV)-oxid in Essigsaure zum primaren Amin (83% d.Th.) hydriert wird, kann durch Zugabe von Essig-saure-athylester die Hydrogenolyse vermieden werden, und man erhalt Bis-[3-methyl-3-(4-methoxy-phenyl)-butyi -hydrazin °. Im 3-Methyl-3-(4-nitro-phenyl)-butanon-(2)-azin wird mit Palladium/Kohle (10%) bei 3,5 bar in Tetrahydrofuran zunachst die Nitro-... [Pg.249]

The heterogeneous catalyst Raney nickel, modified with tartaric acid and sodium bromide, was used in the hydrogenation of 4-hydroxy-2-butanone and 4-methoxy-2-butanone. (/ )- ,3-Buianediol and (/ )-4-mcthoxy-2-butanol were obtained in quantitative yield and in 70 and... [Pg.665]


See other pages where 1- Methoxy-3-butanone is mentioned: [Pg.17]    [Pg.1382]    [Pg.95]    [Pg.17]    [Pg.149]    [Pg.113]    [Pg.414]    [Pg.981]    [Pg.21]    [Pg.285]    [Pg.2372]    [Pg.246]    [Pg.981]    [Pg.124]    [Pg.194]    [Pg.568]    [Pg.436]    [Pg.414]    [Pg.273]    [Pg.528]    [Pg.354]    [Pg.718]    [Pg.88]    [Pg.43]    [Pg.43]    [Pg.388]    [Pg.461]   
See also in sourсe #XX -- [ Pg.295 ]




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Butanone

L-Methoxy-2-butanone

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