2- phenylacetate esters

Silanes can react with acceptor-substituted carbene complexes to yield products resulting from Si-H bond insertion [695,1168-1171]. This reaction has not, however, been extensively used in organic synthesis. Transition metal-catalyzed decomposition of the 2-diazo-2-phenylacetic ester of pantolactone (3-hydroxy-4,4-dimethyltetrahydro-2-furanone) in the presence of dimethyl(phenyl)silane leads to the a-silylester with 80% de (67% yield [991]). Similarly, vinyldiazoacetic esters of pantolactone react with silanes in the presence of rhodium(II) acetate to yield a-silylesters with up to 70% de [956]. 

Methods Primarily of Historical Interest. In the Bouveault-Blanc deduction (79,80) phenylacetic ester is reduced with sodium and alcohol to... 

In Leonard s Method (81) toluene is chloiinated to benzyl chloiide which is, in turn, converted to phenylacetic ester, and then to PEA. 

All lation of Garbanions. Concentrated N a OH—hen syl triethyl amm onium chloride is the base/catalyst system normally used for this type of process (20). Classes of compounds alkylated in this way include phenylacetonitriles, ben2ylketones, simple aUphatic ketones, certain aldehydes, aryl sulfones, P-ketosulfones, P-ketoesters, malonic esters and nitriles, phenylacetic esters, indene, and fluorene (see Alkylation). 

Certain of the monoalkylated ethyl phenylacetates have been further alkylated with alkyl and aralkyl halides to produce the corresponding disuhstituted phenylacetic esters.4 Ethyl 2-phenyl-propanoate has been alkylated by methyl iodide to give pure ethyl 2-methyl-2-pheny]propanoate in 81% yield. Similarly, the alkylations of ethyl 2-phenylhexanoate with methyl iodide, M-butyl bromide, and benzyl chloride gave the corresponding pure dialkylated products in 73%, 92%, and 72% yields, respectively. 

Compounds such as phenylacetate esters and phenylethyl ethers, which have oxygen substituents that can serve as directing groups, show high ortho. para ratios under these conditions.12 These reactions are believed to involve coordination of the N02+ at the substituent oxygen, followed by intramolecular transfer. 

Pyridyl-2-hydroxybenzo[b]furans have been obtained by an unexpected Truce-Smiles type rearrangement of 2-(2 -pyridyloxy)phenylacetic esters 111. Yields of these conversions were not recorded <00TL4541>. 

Synthetic pyrethroids now account for at least 30% of the world insecticide market and are rapidly replacing other agricultural chemicals for control of insect pests. Fenvalerate is one of the more widely used synthetic pyrethroid insecticides. It is derived from a combination of a-cyano-3-phenoxybenzyl alcohol and a-isopropyl phenylacetate ester. Technical fenvalerate is a mixture of four optical isomers, each occurring in equal amounts but with different efficacies against insect pests. Fenvalerate does not usually persist in the environment for >10 weeks, and it does not accumulate readily in the biosphere. Time for 50% loss (Tb 1/2) in fenvalerate-exposed amphibians, birds, and mammals was 6 to 14 h for reptiles, terrestrial insects, aquatic snails, and fish it was >14 h to <2 days and for various species of crop plants, it was 2 to 28 days. Fenvalerate degradation in water is due primarily to photoactivity, and in soils to microbial activity. Half-time persistence in nonbiological materials is variable, but may range up to 6 days in freshwater, 34 days in seawater, 6 weeks in estuarine sediments, and 9 weeks in soils. 

Ester of nor-caradiene carboxylic acid (Pseado-phenylacetic ester)... 

In a similar vein, antibody NPN43C9 appears to employ a catalytic histidine, HisL91, as a nucleophilic catalyst in the hydrolysis of a p-nitrophenyl phenylacetate ester, as discussed in detail below (Section 5 Appendix entry 2.8) (Gibbs et al., 1992a Chen et al., 1993). 

The reactivity of phenylacetic esters with electron-deficient alkenes is generally fairly poor, even under phase-transfer catalytic conditions. The reaction with cinnamic esters is often accompanied by hydrolysis and the yield of the adduct with chalcone is generally <60% [10]. The activity of the methylene group towards alkylation has been enhanced by the initial complexation of the phenyl ring with chromium tricarbonyl (see Section 6.2), but this procedure has not been applied to the Michael reaction. 

Phenylacetic acid Used in the chemical and pharmaceutical industries for the manufacture of phenylacetate esters, amphetamine and some derivatives used for the synthesis of penicillins used in fragrance applications and cleaning solutions. 

However, the ketols 166 and 167, which are similar to compounds 164 and are the products from the condensation of isatin 7 with malononitrile or phenylacetic ester respectively, were transformed into 2-quinolone-4-carboxylic acid 168 or its 3-phenyl derivative 169 [146],... 

Formic ester in sulphuric-acid solution is attacked only with difficulty in the cathode chamber (Tafel and Friedrichs4) acetic ester, cyanacetic ester, and phenylacetic ester, it may be remarked here, are not attacked at 9II. 

Phenylacetamides, to protect amines, 354 p-0-Phenylacetate esters, to protect alcohols, %... 

The tendency toward hydrogenolysis to give hydrocarbons is greatly reduced with phenylacetic esters where a homobenzyl-type alcohol is produced. If the hydrogenation was stopped before the absorption of hydrogen was complete, a 39.7% yield of 2-phenethyl alcohol was obtained over Cu-Ba-Cr oxide even at 250°C. The yield was further increased to 58.3% over Cu-Mg-Cr oxide (eq. 10.20), and the yields from the cyclohexyl ester was 58.7% over Cu-Ba-Cr oxide and 63.3% over Cu-Ca-Cr oxide. In contrast, over a catalyst containing no alkaline-earth metal oxide, the predominant product from the ethyl ester became ethylbenzene (88.7%), and 2-phenethyl alcohol was obtained in only 4.5% yield. 

This reaction gives high product yields and works with a methylbenzyl-cyanide, 9-methylfluorenide anions as well as with the anion of a-meth-ylphenylacetic ester or propiophenone. No reaction is however found with the non methylated anions of phenylacetonitrile, fluorene, phenylacetic ester or acetophenone. The postulated mechanism implies an hydrogen abstraction from an anion leading to a radical anion intermediate ... 

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