Ethyl glycidate, reaction with

The Cl 4-aldehyde 7 is also a key intermediate in the technical synthesis of vitamin A. It can be prepared from p-ionone f7J in a Darzens glycidic ester condensation by the reaction with ethyl chloroacetate (16) via 17 as intermediate. The chain elongation to the Ci9-aldehyde 72 was achieved by reaction with the acetylenic Cs-compound 18 (Scheme 4). 

Azide is a potent nucleophile and can react with electrophilic substrates other than halides and sulfonate esters. Reaction of azide with the epoxide moiety in carboethoxy oxirane (ethyl glycidate) was followed by catalytic hydrogenation of the azide and hydrolysis of the ester to give isoserine (3-amino-2-hydroxypropanoic acid, 1.23). This synthetic approach to isoserine dates to 1879. 3... 

It is a yellow liquid with a powerful, green, cucumber-like and melon odor. It can be prepared by Darzens reaction of 6-methyl-5-hepten-2-one with ethyl chloroacetate. The intermediate glycidate is saponified and decarboxylated to yield the title compound. 

It is prepared by treating ethyl cinnamate with peracetic acid [212] or by condensation of benzaldehyde with ethyl chloroacetate (in the above Darzens reaction, R = H). The glycidate is used as a long-lasting fragrance material for creating harmonic, fruity notes in household and fine fragrances. 

Other preparations of 2-iminothiazolidin-4-ones which are discussed in the review by Brown139 utilize the reactions of thiourea with a-hydroxy acids,146 ethyl diazoacetate,73 glycidic esters,74,147 cinnamic acid,148 unsaturated diacids (fumaric, maleic, and citraconic) or their esters or imides,149-152 and propiolic esters.153,154 There has been considerable controversy in the literature surrounding the propiolic ester synthesis since many workers have proposed that the products are 1,3-thiazines (see Section IV, B, 1). The pertinent papers in this controversy have been summarized by Cain and Warrener.155 Nagase158 has recently settled the argument in favor of the 2-iminothiazolidin-4-... 

Loss straightforward are results secured with aryl-substituted glycidic esters. Difficult to reconcile with the Parker-Isaacs model, for instance, are the reactions (Kqs. 029 and 630) of ethyl 3>penta-methylene glyojdate111 -l115-uz0 and ethyl 3-p-anisylgIyeid te.1128... 

The Darzens reaction of isatin with ethyl chloroacetate yields glycidic esters. Alkaline hydrolysis of the glycidic esters yields indole-2,3-dicarboxylic and indole-3-carboxylic acids in a 6 1 proportion. The isolation of two isomeric glycidic esters, and the fact that both produce the indolecarboxylic acids in the same proportion led to a mechanistic proposal for the formation of the later through a common intermediate439 (Scheme 101). 

This reaction involves the condensation of an aldehyde or ketone with an a-halo ester in the presence of a basic condensing agent (sodium ethoxide, sodamide, finely divided sodium or potassium teri.-butoxide) to give a glycidic (or p-epoxy) ester. Thus acetophenone and ethyl chloroacetate yield phenyl-methyl glycidic ester (I) ... 

B.vi. Tbe Darzens Glycidic Ester Condensation. When an a-halo ester is treated with base and the resulting enolate anion condensed with a carbonyl derivative, the product is an alkoxide. This nucleophilic species can displace the halogen intramolecularly to produce an epoxide, which forms the basis of a classical reaction known as the Darzens glycidic ester condensation. 13S Reaction of ethyl a-chloroacetate and sodium ethoxide, in the presence of benzaldehyde. generated the usual alkoxide (221). Intramolecular displacement... 

The reactions of f-butyl peroxylate anion with ethyl 2-methylene-3-acetoxy-butanoate and with ethyl 2-bromomethylbut-2-enoate have been studied by Mailard and co-workers, respectively (Scheme 3.134). " They found that both reactions resulted in the y-attack products 311 in low yields. However, the allyl f-butyl peroxides 312 were obtained in 45% yield when the reaction was carried out in the presence of poly(ethylene oxide) 400. Subsequently, 312 was converted into the corresponding glycidic ester 313 by heating in benzene. Recently, Chen et al. developed the first peroxo-asymmetric allylic alkylation of bulky hydroperoxyalkanes with MBH carbonates with catalysis by commercially available modified cinchona alkaloids. Peroxides 314 were generally... 

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