Methyl acetyl Ether

Acetoxylation and nitration. It has already been mentioned that 0- and m-xylene are acetoxylated as well as nitrated by solutions of acetyl nitrate in acetic anhydride. This occurs with some other homologues of benzene, and with methyl phenethyl ether,ii but not with anisole, mesitylene or naphthalene. Results are given in table 5.4. 

Ph.CH2.OMe, Ph.(CH2)2.0Me, Ph.(CH2)3.0Me (2-3, 3-4, 1-3), does not decrease steadily, but goes through a maximum. These two circumstances point to a specific -interaction in nitrations of the ethers with acetyl nitrate which is important with benzyl methyl ether, more important with methyl phenethyl ether, and not important with methyl phenpropyl ether. This interaction is the reaction with dinitrogen pentoxide already mentioned, and the variation in its importance is thought to be due to the different sizes of the rings formed in the transition states from the different ethers. 

Methoxyethanoyl chloride, see Methoxy acetyl chloride, 1161 f Methoxyethene, see Methyl vinyl ether, 1217... 

Several polymers were found to fit all or most of the above criteria and were used to prepare the carrier films. Many polymers have been used for this purpose, viz., ethyl cellulose, poly(y-benzyl glutamate), poly(vinyl acetate), cellulose acetate phthalate, and the copolymer of methyl vinyl ether with maleic anhydride. In addition to the base polymers, plasticizers were often needed to impart a suitable degree of flexibility. Plasticizers, which are found to be compatible with polymeric materials include, acetylated monoglycerides, esters of phthalic acid such as dibutyl tartarate, etc. An excipient was usually incorporated into the matrix of the carrier films. The excipients used were water-soluble materials, which are capable of creating channels in the polymer matrix and facilitate diffusion of the drug. PEGs of different molecular weights were used for this purpose. 

The Koenigs-Knorr101102 Reactions" of 3,4,6-Tri-0-acetyl-2-0-benzyl-a- (50a) and -/3-D-Glucopyranosyl Chlorides (50b) and the Perchlorate (50c) with Isopropyl Alcohol and Methyl Trityl Ether at 0°... 

Reactions were performed with 1 molar equivalent of isopropyl alcohol or methyl trityl ether. 6 Analyzed by gas chromatography (g.l.c.). c Analyzed by g.l.c. after acetylation. d Reactions were conducted in the presence of Drierite. Methyl trityl ether was used. 

B5hme procedure involving cleavage of JV -tetramethyl(methylene)diamine (34) with TMS-I. Qeavage of (34) with acetyl chloride in analogy to the Bdhme procedure furnishes the crystalline chloride (31), as does cleavage of methyl dimethylaminomethyl ether with methyltrichlorosilane. The trifluoroacetate (32), unlike the iodide or chloride, is a liquid and is prepared by Polonovski reaction of... 

A major problem with the analysis of 0-acetylated sugars is the determination of the site(s) of 0-acetylation. DeBelder and Norman (1968) have developed a method in which the 0-acetylated polysaccharide is treated with methyl vinyl ether to yield mixed acetals. These are stable to base and methylation of the protected polymer alkylates the position(s) of... 

All of the free hydroxyl groups are protected as acetals by reaction with methyl vinyl ether. The 0-acyl groups are then split off by treatment with alkali, and the resulting material is methylated (see Scheme 20). After hydrolysis of the methylated material, and analysis of the hy-drolyzate as alditol acetates by g.l.c.-m.s., it is possible to determine the positions and proportions of O-methyl groups and, hence, the substitution pattern of the 0-acyl groups. This procedure has been used to locate 0-acetyl groups in bacterial polysaccharides and wood polysaccharides. ... 

Methoxybutane-1,3-dione Methyl acetyl acetate Methyl acetylacetonate Methyl 3-oxobutanoate Methyl 3-oxobutyrate 3-Oxobutanoic acid methyl ester Classification Carboxylic acid ester Empirical CsHsOa Formula CH3COCH2COOCH3 Properties Colorless liq. very sol. in water sol. in alcohol, ether misc. with oxygenated soivs. m.w. 

Methyl acetyl ricinoleate PEG-12 dilaurate PEG-12 dioleate PPG-23 oleyl ether PPG-37 oleyl ether... 

Oleyl erucate PEG-20 sorbitan isostearate PPG-5-ceteth-20 PPG-10 methyl glucose ether PPG-20 methyl glucose ether SD alcohol 27-A SD alcohol 27-B SD alcohol 36 Trihydroxystearin solvent, pharmaceuticals Acetic acid Acetic acid, glacial Acetone Acetonitrile Acetylated mono- and diglycerides of fatty acids Acetyl triethyl citrate n-Amyl alcohol t-Amyl alcohol Apricot kernel oil PEG-6 esters Benzene... 

Acetyl methyl carbinol n-ButyrIc acid 1,4-Dioxane Ethyl acetate Isobutyric acid Isopropyl formate Methyl glycidyl ether Methyl propionate Propyl formate C4H8O2S Sulfolane C4H8O3... 

Weakly acidic phenols that do not react with diazomethane can be methylated with sodium hydride and methyl iodide in THF at room temperature. The methoxymethyl ether moiety can be used to protect phenols. It is stable to alkali, Grignard reagents, lithium aluminum hydride, and catalytic hydrogenation, and is readily removed by mineral acid. Dimethoxymethane can be used in lieu of the carcinogenic chloromethyl methyl ether for this purpose. Alternatively, phenols may be protected as methyl thiomethyl ethers.The (9-acetylation of phenols in the presence of primary and secondary amines can be carried out with acetyl bromide and TFA. ... 

Methyl enol ethers of acyl silanes have been prepared in good yield by the silyla-tion of vinyl lithium reagents derived from methyl enol ethras . Indeed, po-haps the simplest preparation of a methyl enol ether of an acyl silane results from addition of a-methoxyvinyl lithium to chlorotrimethylsilane. Acid hydrolysis gave acetyl trimethyl-silane in ca 80% yield . A similar reaction has been carried out with phenyl methyl (-butyl chlorosilane. Again, acid hydrolysis gave the acyl silane, which is of course chiral at silicon . ... 

Acetophenone. Acetophenone [98-86-2] (methyl phenyl ketone) is a colorless Hquid that forms laminar crystals at low temperature (mp 20°C). It has a characteristic sweet orange blossom odor, and is soluble in alcohols and ethers. It is found in nature in oil of casatoreum, obtained from beavers oil of labdanum, recovered from plants and in buds of balsam poplar. It can be prepared by the Friedel-Crafts reaction (qv) of acetyl chloride with benzene in the presence of aluminum chloride however, this route is of Htde commercial significance. 

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