2- ethy, carbonates

Synthesis of the dibenzofuran (27) by irradiation of grisa-3, 5 -diene-2, 3 -dione (28) is believed to involve electrocyclic ring opening followed by intramolecular cycloaddition to the ketene and elimination of carbon dioxide, as shown in Scheme 2.24 Analogous photocyclizations are responsible for the photochromism exhibited by heterocyclic fulgides such as ( )-a-3-furyl-ethy idene(isopropylidene)succinic anhydride (29), which on irradiation... 

Methylphosphonic acid (MPA), a degradation product of gas chemical warfare agents, such as sarin (isopropyl methylphosphonofluoridate), soman or VX (0-ethy I -.S -2-di isopropyl am i noethvl methyl phosphonoth ioate), has been recognized selectively by an MIP chemosensor using potentiometric transduction (Table 6) [181]. The MIP preparation involved co-adsorption, in ethanol, of the methylphosphonic acid (MPA) template and octadecyltrichlorosilane, followed by silanization on the indium-tin oxide (ITO) electrode surface in the chloroform-carbon tetrachloride solution at 0 °C. Subsequently, the electrode was rinsed with chloroform to remove the template. A potential shift due to the presence of MPA was significant as compared to that due to interferants like methyl parathion, dimethoate, phosdrin, malathion, etc. The linear concentration range varied from 50 pM to 0.62 M MPA at LOD as low as 50 pM and an appreciably short response time of 50 s. 

A 200-ml. three-necked flask is equipped with a thermometer, a mechanical stirrer, a gas inlet tube extending as far into the flask as the stirrer permits, and a trap (designed to return the heavier layer of the condensate) (Note 1), which is attached to a bulb and a coil-type reflux condenser connected in series. Methyl >-ethy 1 benzoate (98 g., 0.597 mole) (Note 2) and a mixture of 1 g. of chromium oxide and 4 g. of calcium carbonate, prepared by grinding the solids together in a mortar, are added. An air line with a bleed control valve (Note 3) is connected from the top of the condenser to a water aspirator. The flask is heated with a hemispherical electric mantle (Note 4). 

Many syntheses of useful compounds utilize the nucleophilic addition of a Grignard or organo-lithium reagent to form carbon-carbon bonds. For example, a key step in the synthesis of ethy-nylestradiol (Section 11.4), an oral contraceptive component, is the addition of lithium acetylide to a ketone, as shown in Figure 20.5. 

Addition of phenol and naphthol in alkaline solution, haa been carried out also with i,2-epoxy-2,4,4-trin)ethy]pentane (Eq. hOl), attack occurring exclusively at the unhindered terminal epoxide carbon atom. ... 

The GO bond or the single C—O bond a constant characteristic value of the interatomic distance is obtained for a number of molecules Table LIII). The case of the double bond C=0 is rather different from that of the ethy-lenic bond G=C, since the C=0 bond is not homopolar and contributions from other valence bond structures, with a separation of charge and a different multiplicity of the bond, always occur. In aldehydes and ketones, for example, the structure > C+—0 contributes to the resonance of the molecule and in carbon dioxide the structure 0 —G O+ occurs. In Table LIV the internuclear. distances of this bond in various molecules is given. In aldehydes the GO bond distance is i-20 A and very probably the same distance occurs in ketones. In urea, because of the contribution of the structure... 

M ethy 1-2-furaldehy de 2-Furfuryl alcohol Carbon dioxide Water Char... 

PVC Di- (2-ethy Uiexy 1) phthalate (DEHP), epoxidized linseed oil, tris(nonyphenyl) phosphite (TNPP) Dissolve in tetrahydrofuran (THE), precipitate polymer with methanol, dry and dissolve residue pPorasil Cjg Carbon tetrachloride- dicloromethane (65/35) 280 1 mL/min [2]... 

Adsorption of sodium bis(2-ethy hexyl)sulfosuccinate from benzene solution onto carbon blacks follows the Langmuir equation and depends on the amount of oxygen on the surface. No adsorption onto heat-treated hydrophobic carbon (Graphon) could be detected (Abram, 1962). 

Fig. 6. I3C CP/MAS NMR spectra of low-density polyethylene (LDPE), copoly(ethy-lene-methacrylic acid) with acid content of 0.054 (E-0.054MAA), and its zinc salt ionomer with a degree of neutralization of 0.9 (E-0.054MAA-0.9Zn) in the aliphatic carbon region at room temperature.

Aromatic and aliphatic acyl isocyanates participate in a similar range of [4 + 2] cycloadditions although [2 + 2] and simple addition reactions often are observed. The acyl isocyanate substituents may determine or alter the observed course of the reaction, and the substituent effects have been detailed in extensive reviews.7,71 Observed [4 + 2] cycloadditions of acyl isocyanates with selected olefins, p-quinones, allenes, the carbon-carbon double bond of ketenes, electron-rich acetylenes, imines, dianils, ethy-lenediimines, enamines, enol ethers, ketene acetals, carbodiimides, azirines, and vinyl sulfides have been described.7 0 The reaction of aromatic acyl isocyanates with carbodiimides is not a simple, direct [4 + 2] cycloaddition but proceeds by a kinetic [2 + 2] cycloaddition followed by a subsequent rearrangement to provide the observed [4 + 2] cycloadduct [Eq. (40)].97... 

White granules. Soly is dependent upon the degree of Substitution. Commercial ethyl cellulose has an ethoxy content of 43-50%. A 47% product softens at ]40° and is sol in ethyl acetate, ethylene dichloride, benzene, toluene, xylene, butyl acetate, acetone, methanol, ethanol, hutanol, carbon tetrachloride. To avoid brittleness, ethy] cellulose formulations usually include an antioxidant such as hydroquinone monobenzyl ether, 4-hexylpyrOcatechol, Or diphenylamine. 

Although cyclic and acyclic carbonates of monosaccharides have been known for some time, little interest had been taken in such derivatives of polysaccharides, probably because the conditions could not be controlled to give any degree of specificity. The formation of cyclic carbonate rings involves treatment of the polysaccharide with ethyl chloro-formate heterogeneous reactions occur, and acyclic carbonate (ethy-oxycarbonyl) groups are also formed. The reaction conditions suitable for maximum cyclic carbonate and minimum acyclic substitution have been investigated in detail for cellulose. Other chloroformates have... 

Ureas, amides and lactams with alpha Hydrogen on a carbon attached to nitrogen N-ethy 1 acetami de,... 

Poly [2-(A, A -dimethy lamino)ethy 1 methacrylate-co-lH,lH-perfluorooctyl methaciylate] carbon dioxide 2008HWA... 

D.H. Jung, Y.K. Ko, and H.T. Jung, Aggregation behavior of chemically attached poly(ethy-lene glycol) to single-walled carbon nanotubes (SWNTs) ropes. Mater. Set Eng. C, 24, 117-121 (2004). 

Barium stearate Benzophenone-12 Cadmium laurate Dimethylsuccinate/tetramethyl hydroxy-1-hydroxyethyl piperidine polymer N-( p-Ethoxycarbony I phenyl )-N -ethy l-N -phenylformamidine 2-(2 -Hydroxy-3,5 -di-t-amylphenyl) benzotriazole 4,4 -lsopropylidenediphenol alkyl (Cl2-15) phosphites Lead carbonate Lead carbonate basic Lead phthalate, dibasic Zinc stearate... 

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