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77-methylpyrrolidone

Arosolvan process A process for the extraction of benzene and toluene from a mixture of aromatic and saturated hydrocarbons using a mixture of water and N-methylpyrrolidone. The process is used when naphtha is cracked to produce alkenes. To prevent extraction of alkenes these are saturated by hydrogenation prior to extraction. [Pg.41]

Alkenes treated with N2O4 and CaO in oxygenated A-methylpyrrolidone are converted into 3-acyl-2-isoxazolines as in Scheme 122 (78USP4069226). [Pg.96]

Sodium sulfide in N-methylpyrrolidone (140°, 2-4 h) cleaves aiyl methyl ethers in 78-85% yield. [Pg.147]

This amide, readily formed from an amine and the anhydride, is readily cleaved by penicillin acylase (pH 8.1, A -methylpyrrolidone, 65-95% yield). This depro-tection procedure works on peptides as well as on nonpeptide substrates. [Pg.354]

In 1973 Du Pont commenced production of another aromatic polytunide fibre, a poly-(p-phenyleneterephthalamide) marketed as Kevlar. It is produced by the fourth method of polyamide production listed in the introductory section of this chapter, namely the reaction of a diamine with a diacid chloride. Specifically, p-phenylenediamine is treated with terephthalyl chloride in a mixture of hexamethylphosphoramide and V-methylpyrrolidone (2 1) at -10°C Figure 18.32). [Pg.514]

Materials of these types have T s of some 290-300°C and some grades are claimed to be stable to about 400°C. Whilst resistant to hydrocarbons, halogenated hydrocarbons, ethers and acids the polymers are soluble in such materials as dimethylformamide, N-methylpyrrolidone and pyridine. Bases can cause stress cracking. These non-crystalline polymers are tough at temperatures as low as -46°C whilst at 260°C they have the strength shown by PTFE at room temperature. The polymers also exhibit excellent electrical insulation properties. [Pg.611]

The close relationship of eegonine to tropine is brought out by its Oxidation products, which when chromic anhydride in acetic acid is the agent used are tropinone, CgHijON (p. 74), tropinic acid, CgHi304N (P- 75) and ecgoninic acid, C HnOgN. The latter crystallises from benzene in colourless needles, m.p. 93°, and has been shown by Willstatter and Bode to W-methylpyrrolidone-2-acetic acid, and this was confirmed by Willstatter and Hollander s synthesis of the acid. [Pg.97]

On treatment with DAST, keto esters undergo oxidative fluorination- ethyl acetoacetate and DAST in W-methylpyrrolidone give a 48-58% yield of a mixture of equal parts of ethyl cis- and trans-2,3-difluoro-2-butenoate [200] (equation 100)... [Pg.242]

Aryl bromides were also perfluoroethylated under these conditions [205] The key to improved yields was the azeotropic removal of water from the sodium perfluoroalkylcarboxylate [205] Partial success was achieved with sodium hepta-fluorobutyrate [204] Related work with halonaphthalene and anthracenes has been reported [206 207] The main limitation of this sodium perfluoroalkylcarboxylate methodology is the need for 2 to 4 equivalents of the salt to achieve reasonable yields A trifluoromethylcopper solution can be prepared by the reaction of bis(tri-fluoromethyl)mercury with copper powder in /V-methylpyrrolidone (NMP) at 140 °C [208] (equation 138) or by the reaction of N-trifluoromethyl-A-nitro-sotnfluoromethane sulfonamide with activated copper in dipolar aprotic solvents [209] This trifluoromethylcopper solution can be used to trifluoromethylate aro matic [209], benzylic [209], and heterocyclic halides [209]... [Pg.703]

Acetone Carbon tetrachloride, chloroform/o-chlorophenol, chloroform// -cresol, chloroform/hexafluoroisopropanol, chloroform/methanol (up to 60%), o-dichlorobenzene, dimethylformamide, dimethyl sulfoxide, dioxane, ethylacetate, FC-113, haxane, methylethylketone, N-methylpyrrolidone, pyridine, quinoline, cyclohexane, dodecane... [Pg.140]

This amide, readily formed from an amine and the anhydride or enzymatically using penicillin amidase, is readily cleaved by penicillin acylase (pH 8.1, A -methylpyrrolidone, 65-95% yield). This deprotection procedure works on peptides, phosphorylated peptides, and oligonucleotides, as well as on nonpeptide substrates. The deprotection of racemic phenylacetamides with penicillin acylase can result in enantiomer enrichment of the cleaved amine and the remaining amide. An immobilized form of penicillin G acylase has been developed. ... [Pg.558]

Mercaptobenzothiazole, A-methylpyrrolidone, DIPEA. The reagent has the advantage that it is odorless and does not lead to intemucleotide cleavage, but the cleavage rate is 10 times slower than when thiophenol is used. ... [Pg.670]

Amine bound to a Wang-polystyrene resin 381 was acylated with 4-oxo-4Ff-pyrido[l,2-u]pyrazine-3-carboxylic acid in the presence of bromotrispyrrolidinophosphonium hexafluorophosphate and /-Pr2NEt in A-methylpyrrolidone (98MIP16). l-(4-Cyclohexyl-4-r / r-butylaminocarbo-nyl-l-piperidyl)-2-(4-fluorophenyl)ethylamine was acylated with perhydro-pyrido[l,2-u]pyrazine-3-carboxylic acid (01MIP19). An amino group of a macrocyclic compound attached to a solid support was acylated with... [Pg.312]

J -methylpyrrolidone by conversion to the imine ( 7) by sequential reaction with triethyloxonium tetraf1uoroborate and then anhydrous ammonia. When this is reacted with 2,6-dimethyl-phenyl i socyanate, the centrally acting muscle relaxant xilobam (8) is formed. ... [Pg.56]

When water-miscible ionic liquids are used as solvents, and when the products are partly or totally soluble in these ionic liquids, the addition of polar solvents, such as water, in a separation step after the reaction can make the ionic liquid more hydrophilic and facilitate the separation of the products from the ionic liquid/water mixture (Table 5.3-2, case e). This concept has been developed by Union Carbide for the hydroformylation of higher alkenes catalyzed by Rh-sulfonated phosphine ligand in the N-methylpyrrolidone (NMP)/water system. Thanks to the presence of NMP, the reaction is performed in one homogeneous phase. After the reaction. [Pg.265]

IV-Methylpyrrolidone (NMP), 156, 302 polyimide synthesis in, 294 Methyl-substituted polycarbosiloxanes,... [Pg.588]


See other pages where 77-methylpyrrolidone is mentioned: [Pg.502]    [Pg.861]    [Pg.568]    [Pg.709]    [Pg.159]    [Pg.73]    [Pg.266]    [Pg.704]    [Pg.115]    [Pg.242]    [Pg.1306]    [Pg.82]    [Pg.83]    [Pg.140]    [Pg.422]    [Pg.430]    [Pg.861]    [Pg.172]    [Pg.132]    [Pg.387]    [Pg.299]    [Pg.25]    [Pg.589]    [Pg.31]    [Pg.32]    [Pg.38]    [Pg.38]    [Pg.38]    [Pg.158]    [Pg.296]    [Pg.296]    [Pg.516]   
See also in sourсe #XX -- [ Pg.493 ]

See also in sourсe #XX -- [ Pg.648 ]




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A?-methylpyrrolidone

Af-methylpyrrolidone (NMP

JV-Methylpyrrolidone

N-Methylpyrrolidone and

N-methylpyrrolidone

TV-Methylpyrrolidone

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