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Methanolic sodium

The iodination reaction can also be conducted with iodine monochloride in the presence of sodium acetate (240) or iodine in the presence of water or methanolic sodium acetate (241). Under these mild conditions functionalized alkenes can be transformed into the corresponding iodides. AppHcation of B-alkyl-9-BBN derivatives in the chlorination and dark bromination reactions allows better utilization of alkyl groups (235,242). An indirect stereoselective procedure for the conversion of alkynes into (H)-1-ha1o-1-alkenes is based on the mercuration reaction of boronic acids followed by in situ bromination or iodination of the intermediate mercuric salts (243). [Pg.315]

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]

Synthetic chemical approaches to the preparation of carbon-14 labeled materials iavolve a number of basic building blocks prepared from barium [ CJ-carbonate (2). These are carbon [ C]-dioxide [ CJ-acetjlene [U— C]-ben2ene, where U = uniformly labeled [1- and 2- C]-sodium acetate, [ C]-methyl iodide, [ C]-methanol, sodium [ C]-cyanide, and [ CJ-urea. Many compHcated radiotracers are synthesized from these materials. Some examples are [l- C]-8,ll,14-eicosatrienoic acid [3435-80-1] inoxn. [ CJ-carbon dioxide, [ting-U— C]-phenyhsothiocyanate [77590-93-3] ftom [ " CJ-acetjlene, [7- " C]-norepinephrine [18155-53-8] from [l- " C]-acetic acid, [4- " C]-cholesterol [1976-77-8] from [ " CJ-methyl iodide, [l- " C]-glucose [4005-41-8] from sodium [ " C]-cyanide, and [2- " C]-uracil [626-07-3] [27017-27-2] from [ " C]-urea. All syntheses of the basic radioactive building blocks have been described (4). [Pg.438]

The side-chain chlorine contents of benzyl chloride, benzal chloride, and benzotrichlorides are determined by hydrolysis with methanolic sodium hydroxide followed by titration with silver nitrate. Total chlorine determination, including ring chlorine, is made by standard combustion methods (55). Several procedures for the gas chromatographic analysis of chlorotoluene mixtures have been described (56,57). Proton and nuclear magnetic resonance shifts, characteristic iafrared absorption bands, and principal mass spectral peaks have been summarized including sources of reference spectra (58). Procedures for measuring trace benzyl chloride ia air (59) and ia water (60) have been described. [Pg.61]

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]

Methyl-3,4-dinitropyrrole (170) undergoes some interesting reactions with nucleophilic reagents. With methanolic sodium methoxide it yields a product (171) which on treatment with trifluoroacetic acid gives the 2-methoxypyrrole (172) 78CC564). [Pg.75]

Isatin (190) is a compound with interesting chemistry. It can be iV-acetylated with acetic anhydride, iV-methylated via its sodium or potassium salt and O-methylated via its silver salt. Oxidation of isatins with hydrogen peroxide in methanolic sodium methoxide yields methyl anthranilates (81AG(E)882>. In moist air, O-methylisatin (191) forms methylisatoid (192). Isatin forms normal carbonyl derivatives (193) with ketonic reagents such as hydroxylamine and phenylhydrazine and the reactive 3-carbonyl group also undergoes aldol condensation with active methylene compounds. Isatin forms a complex derivative, isamic acid (194), with ammonia (76JCS(P1)2004). [Pg.77]

Aminoboranes can be prepared from diborane to protect a tertiary amine during oxidation they are cleaved by refluxing in ethanol or methanolic sodium carbonate. ... [Pg.372]

The following table gives exchange rates in methanolic sodium methoxide for a number of hydrocarbons and equilibrium acidities for some. Determine whether there is a correlation between kinetic and thermodynamic acidity in this series of compounds. If so, predict the thermodynamic acidity of the hydrocarbons for which no values are listed. [Pg.442]

Estrone methyl ether (100 g, 0.35 mole) is mixed with 100 ml of absolute ethanol, 100 ml of benzene and 200 ml of triethyl orthoformate. Concentrated sulfuric acid (1.55 ml) is added and the mixture is stirred at room temperature for 2 hr. The mixture is then made alkaline by the addition of excess tetra-methylguanidine (ca. 4 ml) and the organic solvents are removed. The residue is dissolved in heptane and the solution is filtered through Celite to prevent emulsions in the following extraction. The solution is then washed threetimes with 500 ml of 10 % sodium hydroxide solution in methanol to remove excess triethyl orthoformate, which would interfere with the Birch reduction solvent system. The heptane solution is dried over sodium sulfate and the solvent is removed. The residue is satisfactory for the Birch reduction step. Infrared analysis shows that the material contains 1.3-1.5% of estrone methyl ether. The pure ketal may be obtained by crystallization from anhydrous ethanol, mp 99-100°. Acidification of the methanolic sodium hydroxide washes affords 10-12 g of recovered estrone methyl ether. [Pg.51]

They are cleaved by refluxing in ethanol," methanolic sodium carbonate, TFA, or ammonium chloride. The aminoborane was found to be stable to LDA and KHMDS."... [Pg.593]

Mono-substitution occurs most readily in the stepwise replacement of the halogen substituents of 2,4,6-trichloro-s-triazine with aqueous methanol and sodium bicarbonate (30°, 30 min), the monomethoxy derivative (324) is obtained on heating (65°, 30 min), the disubstitu-ted derivative is formed and on brief heating (65°) with the more basic sodium carbonate or methanolic sodium hydroxide (25°, 3 hr) complete methoxylation (320) occurs. Ethanolic ethoxide (25°, 1 hr) or sodium carbonate (35°) is sufficient to give complete ethoxy-dechlorination. The corresponding phenoxy derivatives are obtained on treatment with one (0°), two (15°, 1 hr), or three equivalents (25-70°, 3 hr) of various sodium phenoxides in aqueous acetone. The stepwise reaction with phenols, alcohols, or thiols proceeds in better yield in organic solvents (acetone or chloroform) with collidine or 2,6-lutidine as acid acceptors than in aqueous sodium bicarbonate. ... [Pg.302]

The corresponding reaction with 2-methylamino-5-nitroaniline affords an unambiguous synthesis of l-methyl-6-nitroquinoxaIin-2-one, the A -mcthyl derivative of (6) this product is also obtained by treatment of (6) with methyl iodide and methanolic sodium methoxided ... [Pg.206]

Preparation of 9, 11 -Epoxy-17a-21 -Dihydroxy-16 -Methyl-4-Pregnene-3 0-Dione 21-Acetate To a stirred solution of 100 mg of the 9a-bromo-11(3,17a,2Ttrihydroxy-16 3-methyl-4-pregnene-3,20-dione 21-acetate in 3 ml of tetrahydrofuran and 1 ml of methanol under nitrogen was added 1.02 ml of 0.215 N methanolic sodium methoxide. After 10 minutes at 25°C, 0.2 ml of acetic acid was added and the methanol removed in vacuo. The residue was acetylated with 1.00 ml of pyridine and 0.5 ml of acetic anhydride at 60°C for 70 minutes. The mixture was taken to dryness in vacuo, water added, and the product extracted into chloroform. The residue was crystallized from ether-acetone to give pure 9(3,11 (3-epoxy-17a,21-dihydroxy-16(3-methyl-4-pregnene-3,20-dione 21-acetate. [Pg.166]

The 3-o-ch orophenvl-5-methvlisoxa2ole4-carboxylic acid, from which the acid chloride was prepared, was obtained by hydrolysis of the ester product of the reaction between o-chloro-benzohydroxamic chlorideand ethyl acetoacetate in methanolic sodium methoxide. Reaction with thionyl chloride gave the starting material. [Pg.386]

A solution of 18 grams of ethyl 2-bromopropionate in 20 ml of tetrahydrofuran is then added to the cooled reaction mixture. After 24 hours at 20°C, the product is hydrolyzed by adding 200 ml of 5 weight percent methanolic sodium hydroxide followed by heating to reflux for 1 hour. The reaction mixture is then diluted with excess 1 N sulfuric acid and extracted with ether. The ether phase Is separated, evaporated to dryness and the residue is recrystallized from acetone-hexane to yield 2-(6-methoxv-2-naphthyl)propionic acid. [Pg.1060]

Step C Preparation of 3-Morpholino-4-(3-tert-Butylamino-2-Oxopropoxy)-1,2,5-Thia-diazole — The 1-toluenesulfonyloxy-2-oxo-3-tert-butylaminopropane, prepared as described in Step B, (11 mols) is added to 0.80 N methanolic sodium methoxide (15 ml) at 0°C. The mixture is stirred for 15 minutes at 0° to 5°C, treated with 3-morpholino-4-hydroxy-1,2,5-thiadiazole (4.29 grams) and then refluxed for 16 hours. The solvent is evaporated in vacuo and the residue is treated with excess potassium carbonate to provide 3-morpholino-4-(3-butylamino-2-oxopropoxy)-1,2,5-thiadiazole. [Pg.1490]

Methyl 2-deoxy-P-v- yxo-hexopyranoside. A suspension of 170 mg. of the nitrobenzoylated hexoside (obtained in the preceding preparation) in 50 ml. of 0.01M methanolic sodium methoxide is stirred for 4 hours at room temperature. The solvent is removed at 40°C. under diminished pressure, and the residue is suspended in 15 ml. of water. The suspension... [Pg.20]

Deethoxycarbonylation of the acetyl derivative 31 is accomplished with methanolic sodium methoxide, and the resulting (i/4-3-acetyl-l//-azepine)tricarbonyliron(0) can be methylated at nitrogen with iodomethane and sodium hydride.226... [Pg.168]

Photolysis of 3-azidoquinolines 4 in the presence of sodium methoxide gives 3-methoxy-3//-l,4-benzodiazepines 5, which rearrange to the 5//-tautomers 6 on heating with methanolic sodium... [Pg.399]

The reactions of methanolic sodium methoxide with 2,4,6-triarylthiopyr-ylium perchlorates 61 have been subjected to many experimental investigations resulting in the chemical picture shown in Scheme 4. [Pg.193]

B. 2,5-Heptanedione. Methanolic sodium methoxide [Methanol, sodium salt] is prepared by cautiously adding small pieces of freshly cut sodium (5.67 g., 0.247 mole) to 200 ml. of cold methanol (Note 3) in a 500-ml., three-nccked flask equipped with a mechanical stirrer, a... [Pg.36]

A portion of the product was heated to reflux with methanolic sodium methoxide to convert it into the thermodynamic mixture of trans- (ca. 65%) and cis- (ca. 35%) isomers. Small amounts of the isomers were collected by preparative gas chromatography using an 8 mm. by 1.7 m. column containing 15% Carbowax 20M on Chromosorb W, and each isomer exhibited the expected spectral and analytical properties. The same thermodynamic mixture of isomers was prepared independently by lithium-ammonia reduction5 of 2-allyl-3-methyl-cyclohex-2-enone [2-Cyclohexen-l-one, 3-methyl-2-(2-propcnyl)-],6 followed by equilibration with methanolic sodium methoxide. [Pg.55]


See other pages where Methanolic sodium is mentioned: [Pg.335]    [Pg.436]    [Pg.85]    [Pg.90]    [Pg.96]    [Pg.100]    [Pg.113]    [Pg.113]    [Pg.127]    [Pg.144]    [Pg.243]    [Pg.63]    [Pg.64]    [Pg.485]    [Pg.151]    [Pg.286]    [Pg.293]    [Pg.107]    [Pg.204]    [Pg.452]    [Pg.650]    [Pg.954]    [Pg.605]    [Pg.61]    [Pg.73]    [Pg.108]    [Pg.623]    [Pg.547]   


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Eluents sodium hydroxide/methanol

Hydrolysis in methanolic sodium hydroxide

Methanol sodium chloride system

Methanol with sodium

Methanol-chloroform, sodium dodecyl

Methanolic sodium hypobromite

Methanolic sodium methoxide

Sodium borohydride-Methanol

Sodium bromide-methanol solutions

Sodium methanol

Sodium methanol

Sodium methanol solutions, physical

Sodium methanolate

Sodium methanolate

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