Methoxy methanol

The formation of the syn adducts has been explained by considering that carboxylic acids or BF3 catalyze the formation of the ionic intermediate by stabilizing the methoxy ion. This intermediate can then collapse directly to the cis product. Reactions in methanol give instead mainly the trans-1,2-adduct, the solvent collapse from the back-side being very rapid. Furthermore, the difference in syn selectivity, slightly larger for 1,4- than for 1,2-addition, has been attributed to a smaller steric hindrance for syn methoxy (methanol) attack at C(4) than at C(2). 

The double reduction of jff-ketoester methoxymethyl enol ethers (88) is reported by an American school o high-yield method for the hydro-genolysis of the /S-carbonyl function treatment with lithium in ammonia causes reduction of the conjugated double bond, elimination of methoxy-methanol, and further reduction to give the saturated ester (89). This procedure is equally effective on the corresponding /3-ketoacids. ... 

A mixture of 3-methoxy-2-nitro-P-pyrrolidinostyrene (lOg, 40 mmol) and Raney nickel (25 g) in methanol-THF (40 ml of each) was heated to 60"C and,... 

When (R) (+) 2 phenyl 2 butanol is allowed to stand in methanol containing a few drops of sulfunc acid racemic 2 methoxy 2 phenylbutane is formed Suggest a reasonable mechanism for this reaction... 

An important question about the mechanism of acid catalyzed esterification concerns the origin of the alkoxy oxygen For example does the methoxy oxygen m methyl benzoate come from methanol or is it derived from benzoic acid s... 

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 ... 

Alkoxyall l Hydroperoxides. These compounds (1, X = OR , R = H) have been prepared by the ozonization of certain unsaturated compounds in alcohol solvents (10,125,126). 2-Methoxy-2-hydroperoxypropane [10027-74 ] (1, X = OR , R" = methyl), has been generated in methanol solution and spectral data obtained (127). A rapid exothermic decomposition upon concentration of this peroxide in a methylene chloride—methanol solution at 0°C has been reported (128). 2-Bromo-l-methoxy-l-methylethylhydroperoxide [98821-14-8]has been distilled (bp 60°C (bath temp.), 0.013 kPa) (129). Two cycHc alkoxyaLkyl hydroperoxides from cyclodecanone have been reported (1, where X = OR R, R = 5-oxo-l, 9-nonanediyl) with mp 94—95°C (R" = methyl) and mp 66—68°C (R" = ethyl) (130). Like other hydroperoxides, alkoxyaLkyl hydroperoxides can be acylated or alkylated (130,131). 

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. 

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. 

Fig. 8. Basic chemistry of acetoxy-based RTV sihcones. The reactions for curing methoxy-based RTV sihcones are the same in that case, the methoxy group (OCH ) replaces acetoxy (OOCCH ), and methanol (CH OH), rather than acetic acid (CH COOH), is formed.

After formation of the acylimine (12), methanol adds to the less sterically hindered a-face of the molecule with high selectivity to provide (13). A further direct incorporation of a 6a-methoxy group (41) and subsequendy a 6a-formamido group into penicillin has been achieved using ttiduoromethanesulfonamides of type (14) (42). 

Nucleophilic aromatic substitutions involving loss of hydrogen are known. The reaction usually occurs with oxidation of the intermediate either intramoleculady or by an added oxidizing agent such as air or iodine. A noteworthy example is the formation of 6-methoxy-2-nitrobenzonitrile from reaction of 1,3-dinitrobenzene with a methanol solution of potassium cyanide. In this reaction it appears that the nitro compound itself functions as the oxidizing agent (10). 

The kinetics of formation and hydrolysis of /-C H OCl have been investigated (262). The chemistry of alkyl hypochlorites, /-C H OCl in particular, has been extensively explored (247). /-Butyl hypochlorite reacts with a variety of olefins via a photoinduced radical chain process to give good yields of aUyflc chlorides (263). Steroid alcohols can be oxidized and chlorinated with /-C H OCl to give good yields of ketosteroids and chlorosteroids (264) (see Steroids). /-Butyl hypochlorite is a more satisfactory reagent than HOCl for /V-chlorination of amines (265). Sulfides are oxidized in excellent yields to sulfoxides without concomitant formation of sulfones (266). 2-Amino-1, 4-quinones are rapidly chlorinated at room temperature chlorination occurs specifically at the position adjacent to the amino group (267). Anhydropenicillin is converted almost quantitatively to its 6-methoxy derivative by /-C H OCl in methanol (268). Reaction of unsaturated hydroperoxides with /-C H OCl provides monocyclic and bicycHc chloroalkyl 1,2-dioxolanes. 

Hydroxyaminopyridazine 1-oxides are usually formed by catalytic hydrogenation of the corresponding nitro derivatives over palladium-charcoal in methanol, provided that the reaction is stopped after absorption of two moles of hydrogen. 3-Hydroxyaminopyridazine 1-oxide and 6-amino-4-hydroxyamino-3-methoxypyridazine 1-oxide are prepared in this way, while 5-hydroxyamino-3-methylpyridazine 2-oxide and 5-hydroxyamino-6-methoxy-3-methylpyridazine 2-oxide are obtained by chemical reduction of the corresponding nitro compounds with phenylhydrazine. 

There is a scattered body of data in the literature on ordinary photochemical reactions in the pyrimidine and quinazoline series in most cases the mechanisms are unclear. For example, UV irradiation of 4-aminopyrimidine-5-carbonitrile (109 R=H) in methanolic hydrogen chloride gives the 2,6-dimethyl derivative (109 R = Me) in good yield the 5-aminomethyl analogue is made similarly (68T5861). Another random example is the irradiation of 4,6-diphenylpyrimidine 1-oxide in methanol to give 2-methoxy-4,6-diphenyl-pyrimidine, probably by addition of methanol to an intermediate oxaziridine (110) followed by dehydration (76JCS(P1)1202). 

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). 

Dipping solution Dissolve 25 mg 2-methoxy-2,4-diphenyl-3(2H)-furanone in 50 ml methanol. 

The hydrogenation of 5a-cholestanone (58) in methanolic hydrobromic acid over platinum gives 3j5-methoxycholestane ° (61). This compound is also obtained from the palladium oxide reduction of (58) in methanol in the absence of acid. Hydrogenation of 5 -cholestanone also gives the 3j5-methoxy product under these conditions. Reduced palladium oxides are quite effective for the conversion of ketones to ethers. The use of aqueous ethanol as the solvent reduces the yield of ether. Ketals are formed on attempted homogeneous hydrogenation of a 3-keto group in methanol. ... 

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°. 

Methoxy-cis-19-norpregna-l,3,5(10),17(20)-tetraene A solution of 31 g (109 mmolesi of estrone methyl ether in 600 ml of benzene is added rapidly to a solution of 469 mmoles of ethylidenetriphenylphosphorane in 1.2 liters of DMSO. After heating under nitrogen at 60° overnight, the reaction is cooled, poured into ice water, and extracted with three portions of hexane, backwashed with three portions of water and the hexane removed. The crude product, dissolved in petroleum ether (bp, 30-60°), is filtered through 225 g of alumina (activity I). The residue from the eluate consists of 95 % cis- and 5 % tran5-isomers, as determined by vpc analysis. After recrystallization from ether-methanol, 26.3 g (82%) of cw-isomer is obtained mp 76.5-77.5° [a]o 60°. 

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