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Sodium with methanol

The reaction is applicable to the preparation of amines from amides of aliphatic aromatic, aryl-aliphatic and heterocyclic acids. A further example is given in Section IV,170 in connexion with the preparation of anthranilic acid from phthal-imide. It may be mentioned that for aliphatic monoamides containing more than eight carbon atoms aqueous alkaline hypohalite gives poor yields of the amines. Good results are obtained by treatment of the amide (C > 8) in methanol with sodium methoxide and bromine, followed by hydrolysis of the resulting N-alkyl methyl carbamate ... [Pg.413]

Treatment of quinoline with cyanogen bromide, the von Braun reaction (17), in methanol with sodium bicarbonate produces a high yield of l-cyano-2-methoxy-l,2-dihydroquinoline [880-95-5] (5) (18). Compound (5) is quantitatively converted to 3-bromoquinoline [5332-24-1], through the intermediate (6) [66438-70-8]. These conversions are accompHshed by sequential treatment with bromine in methanol, sodium carbonate, or concentrated hydrochloric acid in methanol. Similar conditions provide high yields of 3-bromomethylquinoHnes. [Pg.389]

In the piepaiation of ioveisol (12) (41), the key intermediate (23) is prepared from the diacid (20) by the action of thionyl chloride followed by 3-amino-l,2-propanediol. The alcohol groups of (23) are protected as the acetates (25), which is then N-acylated with acetoxyacetyl chloride and deprotected in aqueous methanol with sodium hydroxide to yield (26). N-alkylation of (26) produces ioversol (12). [Pg.465]

Butadienes give a complex mixture of methoxylated products by electrochemical oxidation in methanol with sodium perchlorate as supporting electrolyte [44]. Dimethoxybutenes are formed together with dimers from reaction of medioxybu-tenyl radicals. A platinum anode gives the highest yields of monomeric products while graphite anodes yield only dimeric products. This is a distinction from the... [Pg.40]

Chlorosulfate groups can be readily removed to give the corresponding hydroxyl groups, with retention of configuration, by treatment of a solution of the carbohydrate chlorosulfate in methanol with sodium iodide in aqueous methanol24 immediate liberation of iodine and evolution of sulfur dioxide occur.34 A possible mechanism for the dechlorosulfation reaction involves displacement by iodide at the chlorine atom the initially formed iodine monochloride would react with iodide ion to give iodine and chloride ion. Alternatively, an unstable iodosulfate could be formed as an intermediate.35... [Pg.232]

Compound 2 is also formed by photolysis of the tosylhydrazone sodium salt of bicyclo[2.2.1]hept-2-ene-7-one. In methanol with sodium methoxide, the initially formed norbornenylidene accepts a proton to give the norbornenyl cation and subsequently gives 2 and 3 in a 16 84 ratio.9... [Pg.225]

Reduction of 11-benzyl-l-methyl-1,2,3,4-tetrahydro-6/7-pyrimido[l, 2-b]-isoquinolin-6-one in methanol with sodium borohydride gave m-ll,lla-H-l,2,3,4,ll,lla-hexahydro derivative 41 (88HCA77). [Pg.196]

Treatment of quinoline with cyanogen bromide, the von Braun reaction, in methanol with sodium bicarbonate produces a high yield of l-cyano-2-methoxy-1,2-dihy droquinoline (3). [Pg.1400]

The acetylene substitution reaction proceeds much more rapidly than the related olefin reaction. The acetylene products and starting materials also undergo side reactions such as polymerization concurrently with the substitution. The best yields are obtained when the reactants are diluted with a large excess of amine, or carried out at lower temperatures in methanol with sodium methoxide as the base. Vinylacetylene derivatives can also be prepared by this reaction starting with vinylic halides. For example, ( )-methyl 3-bromo-2-methylpropenoate and r-butylacetylene react in 2 hours at 100° to form the expected vinylacetylene derivative in 59% yield ... [Pg.347]

As to N,N-dialkylhomologues of MDA, the N,N-dimethyl has been separately entered in the recipe for MDDM. Two efforts were made to prepare the N,N-diethyl homologue of MDA. The reasonable approach of reducing a mixture of diethylamine hydrochloride and 3,4-methylenedioxyphenylacetone in methanol with sodium cyanoborohydride was hopelessly slow and gave little product. The reversal of the functionality was successful. Treatment of MDA (as the amine) and an excess of acetaldehyde (as the carbonyl source) with sodium borohydride in a cooled acidic medium gave, after acid-base workup, a fluid oil that distilled at 85-90 °C at 0.15 mm/Hg and was converted in isopropanol with concentrated hydrochloric acid to 3,4-methylenedioxy-N,N-diethylamphetamine (MDDE) with amp of 177-178 °C. Anal. (C14H22ClNO,) N. [Pg.371]

When tellurium bis[(9-ethyl dithiocarbonate] was heated in methanol with sodium dithiocarbamates, tellurium bis[dithiocarbamates] were formed3. [Pg.54]

Evidence to support alternative (b) above stems from an earlier study of the photochemical behavior of vinyl bromide (32) in methanol with sodium meth-oxide, which revealed an increase in the quantum yield of formation of the reduction product with sodium methoxide compared to the irradiation with no sodium methoxide [64]. Sodium methoxide was proposed as the electron transfer reagent however, a chain mechanism with formaldehyde radical anion as the electron transfer reagent as proposed by Bunnett seems more attractive [37g, 65]. [Pg.79]

The disodium salt of oxohyponitrous acid, Angeli s salt, is formed by the nitration of hydroxylamine HONH2 with alkylnitrates RNO3 in methanol with sodium methanolate at 273 K. [Pg.3064]

The methylenedioxypropenylphenol (283) undergoes another form of oxidative dimerization on treatment with palladium(II) chloride in aqueous methanol with sodium acetate. As shown in Scheme 12,... [Pg.697]

NaBHi-Pd-C. Aromatic nitro compounds are not normally reduced by NaBHi but can be reduced smoothly in solution in water or methanol with sodium borohydride catalyzed by 10% palladium charcoal. Azobenzene is reduced by this method to hydrazobenzene and not to aniline. [Pg.530]

Halooxy substitutions. On reinvestigating a curious product obtained by Green and Rowe by treatment of 2,4-dinitroaniline in alkaline methanol with sodium hypochlorite, Mallory and Varimbi established the true structure to be that of 5-chloro-4-methoxybenzofurazane-Toxide (4, in equilibrium with the less stable... [Pg.546]

Derivation By heating methanol with sodium formate and hydrochloric acid with subsequent distillation. [Pg.830]

Reduction of the dimer in methanol with sodium borohydride gives two dia-stereoisomeric tetrahydroserpentinines (251) and (252), whose u.v. spectra... [Pg.288]

The oxadiazole ring was added onto 1 on stirring a saturated solution in methanol with sodium nitrite and hydroxylamine hydrochloride to give dioxime 235. On treatment with sodium carbonate it gave furazan oxide... [Pg.39]

Krivonogov et al. (02RJOC308) (Scheme 22) used basic conditions, N,N-dimethylformamide and methanol with sodium methoxide, to cyclize te-hydrazone 90, whereas Filippone and co-workers (02S1546) (Scheme 22) used acidic conditions, tetrahydrofuran with TFA, to cyclize... [Pg.160]

The 3a-tropanol 0-riboside (23) has been prepared by trans-glycosylation of the amino-alcohol with l-0-acetyl-2,3,5-tribenzoyl-ribofuranose, catalysed by boron fluoride etherate, followed by Zemplen deacylation in methanol, with sodium methoxide as a catalyst. [Pg.61]

Terpenic-type intermediates of use in formation of the side-chain in tocopherols have been derived from myrcene (ref. 118). Thus, a mixture of E- and Z-isomers from its hydrochlorination which resulted in a dichloroderivative containing primary and tertiary halide groups was reacted with trimethylhydroquinone in dioxane/dichloromethane containing zinc chloride, zinc and hydrogen chloride to afford an 89% yield of a chloro intermediate. Dehydrochlorination in methanol with sodium hydroxide afforded a mixture of pentenyl compounds which was isomerised with toluenesulphonic acid in refluxing benzene to 6-hydroxy-2,5,7,8-tetramethyl-2-(4-methyl-3-pentenyl)chroman. The elaboration of the side-chain to produce the tocopherol structure was not described and the synthesis is not stereospecific... [Pg.452]

Borohydride-reduced palladium. Reduction of palladium chloride in methanol with sodium borohydride until evolution of a gas ceases leads to a black material, which is not particularly sensitive to air and is not pyrophoric. The material is useful for selective hydrogenations. It catalyzes rapid hydrogenation of bonds of the type C=C, N=N, and N=0, but not the type C=N and C=0. Nohydrogenolysisof nitrogen or oxygen functions is observed in alcohols, amines, amides, esters, ethers, or lactones. Epoxides are opened to alcohols very slowly. [Pg.446]

Reaction of [Rh(TTP)] with Oxygen. A solution of [Rh(TTP)] in methanol was prepared as described above by the reduction of [Rh-(TTP)Cl2]Cl in methanol with sodium borohydride. Upon exposure to air for 3-5 min, the gold solution turned deep blue initially, and then it rapidly became deep red-brown. At this point, LiC104 dissolved in methanol was added to precipitate the product which was obtained as a brown amorphous solid. The molar conductance (CH3NO0) is 83 cmV ohm mole. [Pg.362]


See other pages where Sodium with methanol is mentioned: [Pg.15]    [Pg.252]    [Pg.36]    [Pg.119]    [Pg.150]    [Pg.137]    [Pg.371]    [Pg.366]    [Pg.540]    [Pg.397]    [Pg.273]    [Pg.234]    [Pg.426]    [Pg.397]    [Pg.454]    [Pg.373]    [Pg.374]   
See also in sourсe #XX -- [ Pg.26 ]




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With methanol

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