Dicarboxylic acid ester diethyl phthalate

Russell and coworkers had found that treatment of dimsyl anion 88 or of a similar methylsulfonyl carbanion with 1,2-, 1,3- and 1,4-dicarboxylic acid esters can give five- to seven-membered cyclic compounds. By this type of cyclization, they prepared ninhydrin hydrate 106 from diethyl phthalate . 

A lot of plasticizers typically with two ester groups have been described in the literature [39] including aliphatic diesters of phthalic acid, like diethyl phthalate, and diesters of aliphatic dicarboxylic acids like dibutyl adipate or azelate [22] as well as glycerol triacetate (triacetin), citrate esters, and phosphates [39]. Although these kind of plasticizers work well for decades in various applications, the accelerated retention test shows [39] that exudation and volatilization must be taken into account and can cause changes in the material performance. Thus, attempts have been made to synthesize long-chain esters of cellulose (LCCEs) with acid chain lengths of up to 20 carbon atoms (see [21] and references cited therein), which could be processed without external plasticizers. Positive results are reported for cellulose acetate hexanoate and cellulose acetate nonanoate [21] but these esters did not go into production. 

Diethyl Phthalate 1,2-Benzene-dicarboxylic Acid, Diethyl Ester Ethyl Phthalate Phthalic Acid, Diethyl Ester ... 

The disappearance of a plasticizer from water can be the result of a number of abiotic and biotic processes that can transform or degrade the compound into daughter compounds that have different physicochemical properties from the parent compound. Hydrolysis is a family of chemical reactions where a plasticizer reacts with water. Phthalate esters may hydrolyze to form monoesters and then dicarboxylic acid. It has been predicted that di-(2-ethylhexyl) sebacate will form 2-ethylhexanol and decanedioic acid. Wolfe et al experimentally measured second-order alkaline hydrolysis rate constants for dimethyl, diethyl, di-n-butyl, and di-(2-ethylhexyl) phthalates, and it appears that hydrolysis may be too slow to have a major impact on the fate of most dissolved plasticizers. The estimated hydrolysis half-lives at pH 7 for 20 plasticizers were longer than 100 days. No information was located for diallyl, ditridecyl and diundecyl phthalates. Under alkaline conditions, hydrolysis may be important for tricresyl phosphate and tri-(2-ethylhexyl) trimellitate at pH 8 their predicted half-lives are 3.2 and 12 days respectively. 

Presumably for similar reasons, cathodic reduction of diethyl terephthalate and diethyl furan- and thiophene-2,5-dicarboxylate [51-53] in a buffered ethanolic solution of pH 4.2 affords the aldehyde ester under controlled potential electrolysis (CPE) conditions (in the interval between —1.50 and —1.65 V). Diethyloxalate [77] is reduced at a mercury cathode in acidic medium to give the ethyl hemiacetal of ethyl glyoxylate (38-50% yield). In contrast, diethyl and monoethyl phthalate gave phthalide under similar conditions [21,78]. 

DEP ethyl benzene-1,2-dicarboxylate ethyl phthalate Koda-flex DEP phthalic acid diethyl ester. 

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