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2-methoxy-, sodium

PECH was modified under similar reaction conditions, except that dimethylformamide (DMF) was used as the reaction solvent. In addition, the phase-transfer-catalyzed etherification of the chloromethyl groups of PECH with sodium 4-methoxy -4 -biphenoxide was used to synthesize PECH with direct attachment of the mesogen to the polymer backbone. Similar notations to those used to describe the functionalized PPO are used for functionalized PECH. In this last case, PPO was replaced with PECH. Esterification routes of both PPO and PECH are presented in Scheme I. [Pg.99]

Bis[4-methylphenyl] Tellurium Bis[2-(4 -methylbenzylidenamino)phenoxide]4 A solution of sodium methoxi-de in 30 ml absolute methanol, prepared by the addition of 0.95 g (40 mmol) sodium to methanol, is added to a stirred solution of 9.40 g (20 mmol) of bis [4-methylphenyl] tellurium dibromide in 50 ml dry toluene. Methanol is distilled from the reaction mixture until the temperature of the vapors reach 110°. Sodium bromide is removed by filtration, The filtrate, containing his[4-methylphenyl] tellurium dimethoxide, is added to a stirred solution of 8.44 g (40 mmol) of 2-(4-methylbenzylidenamino)phenol in 50 ml dry toluene. Most of the toluene is distilled under vacuum from the reaction mixture. The concentrate ( 30 ml) is mixed with an equal volume of absolute diethyl ether. The mixture is cooled to — 5°. The crystals are collected by filtration and recrystallized from hexane m.p. 135°. [Pg.601]

See Sodium methoxy acetylide Brine See other acetylenic compounds... [Pg.407]

The reaction of MeO /MeOH with 2-Cl-5(4)-X-thiazoles (122) follows a second-order kinetic law, first order with respect to each reactant (Scheme 62) (297, 301). A remark can be made about the reactivity of the dichloro derivatives it has been pointed out that for reactions with sodium methoxide, the sequence 5>2>4 was observed for monochlorothiazole compounds (302), For 2.5-dichlorothiazole, on the contrary, the experimental data show that the 2-methoxy dehalogenation is always favored. This fact has been related to the different activation due to a substituent effect, less important from position 2 to 5 than from... [Pg.408]

Salts composed of an anion, RO—, and a cation, usually a metal, can be named by citing first the cation and then the RO anion (with its ending changed to -yl oxide), e.g., sodium benzyl oxide for CgH5CH20Na. However, when the radical has an abbreviated name, such as methoxy, the ending -oxy is changed to -oxide. For example, CHjONa is named sodium methoxide (not sodium methylate). [Pg.26]

Diuretics. Chlomieodrin [62-37-3] (methoxy(urea)propylmercuric chloride) (8), is prepared ia the same sort of reaction used for chloromethoxypropylmercuric acetate. Ahyl urea is used instead of aHyl chloride, together with methanol and mercuric acetate. The product, after dilution with water and neutralization, is precipitated with sodium chloride ... [Pg.116]

Unsaturation value can be determined by the reaction of the akyl or propenyl end group with mercuric acetate ia a methanolic solution to give acetoxymercuric methoxy compounds and acetic acid (ASTM D4671-87). The amount of acetic acid released ia this equimolar reaction is determined by titration with standard alcohoHc potassium hydroxide. Sodium bromide is normally added to convert the iasoluble mercuric oxide (a titration iaterference) to mercuric bromide. The value is usually expressed as meg KOH/g polyol which can be converted to OH No. units usiag multiplication by 56.1 or to percentage of vinyl usiag multiplication by 2.7. [Pg.352]

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]

The primary synthesis of alkoxypyrimidines is exemplified in the condensation of dimethyl malonate with O-methylurea in methanolic sodium methoxide at room temperature to give the 2-methoxypyrimidine (854) (64M207) in the condensation of diethyl phenoxymalonate with formamidine in ethanolic sodium methoxide to give the 5-phenoxypyrimidine (855) (64ZOB1321) and in the condensation of butyl 2,4-dimethoxyacetoacetate with thiourea to give 5-methoxy-6-methoxymethyl-2-thiouracil (856) (58JA1664). [Pg.134]

The O-alkyl derivatives of those A-oxides, which exist partly or entirely as (V-hydroxy tautomers, may be made by primary synthesis (as above) or by alkylation. Thus, 5,5-diethyl-1-hydroxybarbituric acid (936 R = H) with methyl iodide/sodium ethoxide gives the 1-methoxy derivative (936 R = Me) or with benzenesulfonyl chloride/ethoxide it gives the alkylated derivative (936 R = PhS02) (78AJC2517). [Pg.142]

After the initial claim of the synthesis of an oxirene (by the oxidation of propyne Section 5.05.6.3.1) this system reappeared with the claim 31LA(490)20l) that 2-chloro-l,2-diphenyl-ethanone (110) reacted with sodium methoxide to give diphenyloxirene (111), but it was later shown (52JA2082) that the product was the prosaic methoxy ketone (112 Scheme 97) (the formation of 111 from 110 would be an a-elimination carbene-type reaction). Even with strong, nonnucleophilic bases, (110) failed to provide evidence of diphenyloxirene formation (64JA4866). [Pg.126]

The a-naphthyldiphenylmethyl ether was prepared to protect, selectively, the 5 -OH group in nucleosides. It is prepared from a-naphthyldiphenylmethyl chloride in pyridine (65% yield), and cleaved selectively in the presence of a p-methoxy-phenyldiphenylmethyl ether with sodium anthracenide, a (THE, 97% yield). The p-methoxyphenyldiphenylmethyl ether can be cleaved with acid in the presence of this group. [Pg.62]

This method is an adaptation of that of Dengel. -Methoxy-phenylacetonitrile can also be prepared by the metathetical reaction of anisyl chloride with alkali cyanides in a variety of aqueous solvent mixtures by the nitration of phenylaceto-nitrile, followed by reduction, diazotization, hydrolysis, and methylation 1 by the reduction of ct-benzoxy- -methoxy-phenylacetonitrile (prepared from anisaldehyde, sodium cyanide, and benzoyl chloride) and by the reaction of acetic anhydride with the oxime of -methoxyphenylpyruvic acid. ... [Pg.52]

A remarkable feature of the Birch reduction of estradiol 3-methyl ether derivatives, as well as of other metal-ammonia reductions, is the extreme rapidity of reaction. Sodium and -butyl alcohol, a metal-alcohol combination having a comparatively slow rate of reduction, effects the reduction of estradiol 3-methyl ether to the extent of 96% in 5 minutes at —33° lithium also effects complete reduction under the same conditions as is to be expected. Shorter reaction times were not studied. At —70°, reduction with sodium occurs to the extent of 56 % in 5 minutes, although reduction with lithium is virtually complete (96%) in the same time. (The slow rates of reduction of compounds of the 5-methoxytetralin type is exemplified by 5-methoxy-tetralin itself with sodium and f-butyl alcohol reduction occurs to the extent of only 50% in 6 hours vs. 99+% with lithium.) The iron catalyzed reaction of sodium with alcohols must be very fast since it competes so well with the rapid Birch reduction. One cannot compensate for the presence of iron in a Birch reduction mixture containing sodium by adding additional metal to extend the reaction time. The iron catalyzed sodium-alcohol reaction is sufficiently rapid that the aromatic steroid still remains largely unreduced. [Pg.22]

Recently reductions by a new hydride reagent, sodium bis(2-methoxy-ethoxy)aluminum hydride, have been investigated. This compound is similar to LiAlH4 in its reducing properties but because it is soluble in aromatic hydrocarbons and more stable in air than LiAlH4, it may be more convenient to use. [Pg.63]

Ji-Methoxy-ll, 11-ethylenedioxy-lS-methylestra-1,3,5(lO)-tnene. A solution of (+)3-methoxy-18-methylestra-l,3,5(10)-trien-17-one (5 g) dissolved in ethylene glycol (5 ml) and ethyl orthoformate (10 ml) containing />-toluenesulfonic acid (0.3 g) is heated under reflux for 2 hr in a nitrogen atmosphere. The resulting solution is diluted with methylene chloride and washed with dilute sodium bicarbonate and water. The organic phase is dried over sodium sulfate and evaporated to dryness in the presence of a trace of pyridine. Trituration of the residue with petroleum ether yields 4.7 g (82 %) of the pure ketal. [Pg.407]

Acetylene is passed for 1 hr through a mixture consisting of 0.5 g (72 mg-atoms) of lithium in 100 ml of ethylene-diamine. A solution prepared from 1 g (3.5 mmoles) of rac-3-methoxy-18-methylestra-l,3,5(10)-trien-I7-one and 30 ml of tetrahydrofuran is then added at room temperature with stirring over a period of 30 min. After an additional 2 hr during which time acetylene is passed through the solution the mixture is neutralized with 5 g of ammonium chloride, diluted with 50 ml water, and extracted with ether. The ether extracts are washed successively with 10% sulfuric acid, saturated sodium hydrogen carbonate and water. The extract is dried over sodium sulfate and concentrated to yield a solid crystalline material, which on recrystallization from methanol affords 0.95 g (87%) of rac-3-methoxy-18-methyl-17a-ethynyl-estra-l,3,5(10)-trien-17jB-ol as colorless needles mp 161°. [Pg.73]


See other pages where 2-methoxy-, sodium is mentioned: [Pg.401]    [Pg.925]    [Pg.428]    [Pg.239]    [Pg.466]    [Pg.83]    [Pg.418]    [Pg.16]    [Pg.32]    [Pg.83]    [Pg.88]    [Pg.90]    [Pg.92]    [Pg.96]    [Pg.97]    [Pg.100]    [Pg.133]    [Pg.7]    [Pg.191]    [Pg.192]    [Pg.195]    [Pg.230]    [Pg.296]    [Pg.321]    [Pg.326]    [Pg.461]    [Pg.463]    [Pg.494]    [Pg.495]    [Pg.543]    [Pg.7]    [Pg.30]   


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