Diethyl acetal

M-Butyl formate. Ethyl iso-butyrate IsO -butyl acetate Ethyl butyrate -Propyl propionate Iso-amyl formate, -But> l acetate Iso-propyl butyrate Iso-butyl propionate n-Propyl -butyrate -Butyl propionate Iso-butyl isobutyrate Ethyl lactate Iso-butyl butyrate Cycloheicyl formate -Butyl -butyrate Iso-propyl lactate. Cyclohexyl acetate Diethyl oxalate Di-iao-propyl oxalate... 

Acetic acid-water Pinched system Ethyl acetate, propyl acetate, diethyl ether, dichloroethane, butyl acetate ... 

Distilled water, high-performance liquid chromatography grade Acetone, ethyl acetate, diethyl ether, acetonitrile, n-hexane, benzene, pesticide residue analysis grade... 

Soluble in acetone, ethyl acetate, diethyl ether, chloroform, and methylene chloride. 

The reaction was then concentrated and the residue was passed through a short column of silica gel eluting with ethyl acetate-diethyl ether (1 1) to remove the catalyst. The (,S )-dimethyl methylsuccinate does not need any further purification (190 mg, 95%). 

Another example of type iii-a is the trifluoromethylation of double bonds by electrolysis of trifluoroacetic acid in the presence of olefins. Methyl vinyl ketone, vinyl acetate, diethyl fumarate, diethyl maleate, Ai-ethylmaleimide, and 2,5-dihydrothiophene-l,1-dioxide were examined as olefins. The products were bis-trifluoromethylated additive dimers (66) (type iii-a) and monomers (67) (type... 

Pan, I.-C., Tang, M., and Chen, Y.-P. Densities and viscosities of binary liquid mixtures of vinyl acetate, diethyl oxalate, and dibutyl phthalate with normal alkanols at 303.15 K, J. Chem. Eng. Data, 45(6) 1012-1015, 2000. 

A mixture of 5.54 g (40 mmol) of 3-methylpentanedioic acid, 14.8 g (80 mmol) of methyl (R)-2-thioxo-4-thi-azolidinecarboxylate, 18.16 g (88 mmol) of dicyclohexylcarbodiimide, and 100 mL of pyridine is stirred at r.t. for 6 d. After evaporation of the excess solvent in vacuum, the residue obtained is treated with 150 mL of benzene, the precipitated urea is filtered off and the filtrate is condensed in vacuum to give 50 mL of solution. Flash-chromatography on a short silica gel column with benzene/ethyl acetate (10 1) affords yellow needles yield 13.0 g (70%) mp 113-114°C (ethyl acetate/diethyl ether) [a] —163.9 (c = 1.00, ethyl acetate). 

CALB, vinyl acetate, Diethyl ether room temp., 2 h, 60%, > 98% . 

Abietic ACID, 32, 1 add sodium salt of, 32, 4 diamylamine salt of, 32, 2 Acetaldehyde, 36, 60 Acetaldehyde, diphenyl-, 38, 26 Acetal diethyl, of acetylenic aldehydes, 39, 60... 

Crosslinking monomers include N-methylol acrylamide, acrylamide, further, acrylamidobutyraldehyde, dimethyl acetal, diethyl... 

Calcium Diazide Dihydraxinate (formerly called Calcium Trinitride Dihydrazinate) Ca(Ns)a 2NaH4, mw 188.22, N 74.37 wh, rect, ortho rhombic crysts, mp dec-slowly at RT, bp exp violently at 335°i v sol in w, sol in anhyd hydrazine (34.7% at 23°), mod sol in methanol ([7% at 23 v si sol in ale (0.4% at 23°) pract insol in CC14, chlf, benz, acet, diethyl eth, et acetate or CS3. Prepd from a nearly satd soln of Ca(Ns)3 in anhyd hydrazine by either evapn at RT over sulfuric acid or treatment with absol ale. Chemical identity established by means of press-concn and press-temp curves in addn to chemical analysis (Refs 1 2)... 

Figure D1.6.2 TLC-FID separation of lipids recovered from the gastric contents of a hooded seal pup. The mobile phase was 91 6 3 1 (v/v/v/v) hexane/ethyl acetate/diethyl ether/formic acid. Time refers to scanning time of the Chromarod. Abbreviations DG, 1,2-diglyceride FFA, free fatty acid MG, monoglyceride IS, internal standard TG, triglyceride. Reproduced from Ackman and Heras (1997) with permission from AOCS Press.

NOTE When using solvents that absorb a lot of water (e.g., ethyl acetate, diethyl ether) it is necessary to dry the extract a second time with anhydrous magnesium sulfate (1 g/10 ml sample). This gives samples that are ready for gas chromatography that are lOOOx more concentrated than the original sample. 

Commonly used extraction solvents are ethyl acetate, diethyl ether, methanol, and aqueous methanol, but the majority of the free phenolic compounds can be extracted with alcohols (methanol or ethanol) or alcohol-water mixtures (1). Due to the differences in polarity between components (40), neither diethyl ether nor ethyl acetate are able to extract completely all the phenolic compounds in a liquid-liquid extraction. Thus, successive extraction with diethyl ether and then ethyl acetate has been used for phenolics in fruit juices (41). When using alcohol-water mixtures (40), repeated extraction or reflux for 1 h are necessary to extract free phenolic acids as well as their glycosides. 

Terpolymers made from two different olefins and CO are known. They were first described in Brubaker s initial patent and involved the free radical initiated terpolymerization of CO and C2H with another olefin such as propylene, isobutylene, butadiene, vinyl acetate, diethyl maleate or tetrafluoroethylene More recently, in another patent, Hammer has described the free radical initiated terpolymerization of CO and C2H with vinyl esters, vinyl ethers or methyl methacrylate 26Reaction temperatures of 180-200 °C and a combined pressure of 186 MPa were employed. Typically a CO QH4 olefin molar ratio of 10 65 25 was observed in the terpolymers. In other patents, Hammer 27,28) has described the formation of copolymers with pendant epoxy groups by the free radical initiated polymerization of CO, QH4, vinyl acetate and glycidyl methacrylate. Reaction conditions similar to those stated above were employed, and a typical CO C2H vinyl acetate glycidyl methacrylate molar ratio of 10 65 20 5 was observed in the product polymer. 

To the suspension of 12.8 g of 2-methyl-3,4-dioxo-l,3,4,14b-tetrahydro-10H-pyrazino[l,2-a]pyrrolo[2,l-c][l,4]benzodiazepine in 460 ml of tetrahydrofuran, 200 ml of 1-molar diborane in tetrahydrofuran are added while stirring and cooling with ice. The mixture is refluxed for one hour, again cooled and combined with 25 ml of acetic acid. It is evaporated, the residue taken up in 50 ml of 30% aqueous sodium hydroxide and the mixture extracted with methylene chloride. The extract is dried, evaporated, the residue dissolved in diethyl ether, the solution filtered and the filtrate evaporated, to yield the crude 2-methyl-l,3,4,14b-tetrahydro-10H-pyrazino[l,2-a]pyrrolo[2,l-c][l,4]benzodiazepine. It is triturated with ethyl acetate-diethyl ether, chromatographed on 70 g of silica gel and eluted with methanol-chloroform (1 9). The eluate is evaporated and the residue salified. 

Ethyl hexanoate and octanoate were the predominant FA esters found in Tinta Negra wines, whereas diethyl succinate and ethyl lactate were the most abundant diprotic acid ethyl esters. According to the authors, the most sensory important flavors seem to be attributed to 3-methylbutan-l-ol, 2-phenylethanol, isoamyl acetate, diethyl succinate, 2-phenylethylace-tate, phenylacetaldehyde, y-nonalactone, ethyl hexanoate, ethyl octanoate, hexanoic acid, and octanoic acid. 

Table 2 also indicates that the nucleophiles effective for vinyl ethers are relatively mild, when compared with those for isobutene (cf., Section V.B.2). In fact, stronger bases lead to inhibition or severe retardation of polymerization [36,64] ketones aldehydes, amides, acid anhydrides, dimethyl sulfoxide (retardation) alcohols, aliphatic amines, pyridine (inhibition). The choice of nucleophiles is determined by their Lewis basicity (as measured by pKb, etc. [64,103]), and this factor determines the effic-tive concentrations of the nucleophiles. For example, the required amounts of esters and ethers decrease in the order of increasing basicity (i.e., a stronger base is more effective and therefore less is needed) [101,103] tetrahydrofuran < 1,4-dioxane ethyl acetate < diethyl ether. On the other hand, for amines not only basicity but also steric factors play an important role [142] thus, unsubstituted pyridine is an inhibitor, while 2,5-dimethylpyridine is an effective nucleophile for controlled/living polymerization, although the latter is more Lewis basic. 

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