Alkyl carboxylate

Function 3 affects performance as determined by the chemistry of alkylate, carboxyl, sulfonyl, phenolic, phosphate, pyrophosphate, and phosphite groups. 

Three generations of latices as characterized by the type of surfactant used in manufacture have been defined (53). The first generation includes latices made with conventional (/) anionic surfactants like fatty acid soaps, alkyl carboxylates, alkyl sulfates, and alkyl sulfonates (54) (2) nonionic surfactants like poly(ethylene oxide) or poly(vinyl alcohol) used to improve freeze—thaw and shear stabiUty and (J) cationic surfactants like amines, nitriles, and other nitrogen bases, rarely used because of incompatibiUty problems. Portiand cement latex modifiers are one example where cationic surfactants are used. Anionic surfactants yield smaller particles than nonionic surfactants (55). Often a combination of anionic surfactants or anionic and nonionic surfactants are used to provide improved stabiUty. The stabilizing abiUty of anionic fatty acid soaps diminishes at lower pH as the soaps revert to their acids. First-generation latices also suffer from the presence of soap on the polymer particles at the end of the polymerization. Steam and vacuum stripping methods are often used to remove the soap and unreacted monomer from the final product (56). 

Reaction conditions depend on the reactants and usually involve acid or base catalysis. Examples of X include sulfate, acid sulfate, alkane- or arenesulfonate, chloride, bromide, hydroxyl, alkoxide, perchlorate, etc. RX can also be an alkyl orthoformate or alkyl carboxylate. The reaction of cycHc alkylating agents, eg, epoxides and a2iridines, with sodium or potassium salts of alkyl hydroperoxides also promotes formation of dialkyl peroxides (44,66). Olefinic alkylating agents include acycHc and cycHc olefinic hydrocarbons, vinyl and isopropenyl ethers, enamines, A[-vinylamides, vinyl sulfonates, divinyl sulfone, and a, P-unsaturated compounds, eg, methyl acrylate, mesityl oxide, acrylamide, and acrylonitrile (44,66). 

Propionates and higher aliphatic esters generally become less toxic as the si2e of the alkyl carboxylate increases. As an example, the LD q (rat, oral) for ethyl nonanoate [123-29-5] is greater than 43 g/kg, and the LD q (rat, oral) for ethyl heptanoate [106-30-9] is 34.6 g/kg. 

M COOH. Likewise, normal insertion into M-C yields alkyl carboxylates M OOCR, though metalloacid esters M COOR are sometimes obtained. The reactions have obvious catalytic implications and arc being actively studied at the present time by several groups. ... 

Several 7-substituted (H, halogen, alkoxy, alkylthio, halogen, alkyl, carboxyl) oxazolo[5,4-/i]quinolines were found to be very effective against broadleaf weeds (90EUP1, 90GEP1). 

The aerobic reduction of aryl and alkyl carboxylates to the corresponding aldehydes. The reaction involves formation of an acyl-AMP intermediate by reaction of the carboxylic acid with ATP NADPH then reduces this to the aldehyde (Li and Rosazza 1998 He et al. 2004). The oxidoreductase from Nocardia sp. is able to accept a range of substituted benzoic acids, naphthoic acids, and a few heterocyclic carboxylic acids (Li and Rosazza 1997). 

Alkylation of the 1,2,4-triazole ring by alkyl radical species has been achieved reaction of 1-methyl-1,2,-4-triazole 37 with alkyl carboxylic acids in the presence of a silver catalyst gave the corresponding 2-alkylated triazoles 38a-e in moderate yields (Equation 9 and Table 1) <2001TL7353>. 

The reaction of benzo-2-furancarboxylic acid with thiosemicarbazide under microwave conditions enables the use of an equivalent amount of phosphorus oxychloride and a short reaction time <2003SC2891 >. Moreover, solvent-free conditions are achieved when acidic alumina is used as dehydrating agent under microwave heating in the reaction of alkyl carboxylic acids with thiosemicarbazide <2000SC3031>. 

Racemic fra .s-A--benzyl-2.5-bis-(ethoxycarbonyl)pyrrolidine has been resolved via its dicarboxylic acid, followed by subsequent transformation to offer (2R,5R)-21 or (25,5S -21. The absolute configuration of the alkylated carboxylic acids indicates that the approach of alkyl halides is directed to one of the diastereotopic faces of the enolate thus formed. In the following case, the approached face is the 57-face of the (Z)-enolate. By employing the chiral auxiliary (2R,5R)-21 or its enantiomer (25.55)-21. the (/ )- or (S)-form of carboxylic acids can be obtained with considerably high enantioselectivity (Table 2-4). 

An interesting preparation of alkyl carboxylates in high yield (Table 3.14) from the sodium salt of the carboxylic acids under mild phase-transfer catalytic conditions involves their reaction with alkyl chlorosulphate [50] and has been used with success in the preparation of alkyl esters derived from p-lactam antibiotics. The procedure is also excellent for the production of chloromethyl esters, particularly where the carboxylic acids will not withstand the classical Lewis acid-catalysed procedure using an acid chloride and formaldehyde, or where the use of iodochloromethane [51] results in the formation of the bis(acyloxy)methane. The procedure has been applied with some success to the synthesis of chloromethyl A-protected a-amino carboxylates [52],... 

This behavior is what would be expected for a two-state, ground-state ionization. The pKa obtained from the pH at which the amplitudes associated with the two decay constants are equal compares well with that of alkyl carboxyl groups of similar compounds. 9,40)... 

Eor univalent ionic surfactants, e.g., alkyl trimethyl-ammonium bromide and chloride, sodium alkyl sulfate, and sodium alkyl carboxylate. 

On the other hand, the slopes obtained were -0.5 for disodlum alkyl phosphate, -0.54 for alkyl trlmethyl-ammonlumchloride,-0.52 for sodium alkyl carboxylate, and -0.58for sodium alkyl sulfate. These values are close to those for nonionic and zwltterionlc surfactants, obtained from the linear relation of log cmc and n. The J4G(CH2) values calculated from Equation 21... 

Janssen, A. J. M. Klunder, A. J. H. Zwanenburg, B. Resolution of secondary alcohols by enzyme-catalyzed transesterification in alkyl carboxylates as the solvent. Tetrahedron 1991, 47, 7645-7662. 

Transition into the Kolbe region at platinum is associated with the formation of an oxide layer. Acetate ions are believed to be more strongly adsorbed on this layer than is water. Conversion of water to oxygen is then suppressed in favour of the oxidation of acetate ions [59, 60. Electron transfer from acetate is synchronous with cleavage of the alkyl-carboxylate bond leaving adsorbed carbon dioxide and... 

The Friedlander condensation of 2,6-diaminopyridine-3,5-dicarbaldehyde (393) with various ketones has been reported (77JOC3410). Reaction of the aldehyde with acetophenone, with deoxybenzoin and with a-tetralone generates the 5,10-dihydro-l,9,10-anthyridine derivatives (394 R = H), (394 R = Ph) and (395) respectively, whilst with acenaphthenone the nonacyclic anthyridine (396) is obtained. The condensation between 2-amino-3-ethoxy-carbonyI-l,8-naphthyridine (225) and alkyl carboxylates under basic conditions produces 4-hydroxy-1,9,10-anthyridin-2-ones (397) (79BAP571). 

From the archival enthalpies of formation of the other species, the enthalpy of formation of cyclohexyl methyl amine is —145.4 kJmoH. From equation 11, the enthalpy of formation of the corresponding salt is —501.2 kJmoH. Attempts to estimate an enthalpy of formation for A-methyldodecanamide reveals a paucity of data to work with, primarily for unsubstituted and A-methylamides . There is much enthalpy of formation data for w-alkyl carboxylic acids, including dodecanoic acid. The methylene increment... 

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