Benzoylacetic ethyl ester

ETHYL BENZOYLACETATE (Acetic acid, benzoyl-, ethyl ester)... 

J>-Benzoqumone, 35, 26 Benzoylacetanilide, 37, 2 Benzoylacetic acid, ethyl ester, 37, 3 Benzoylacetic acid, ethyl ester, 37, 32 Benzoylation, of o-hydroxyacetophenone, 32, 72... 

It is difficult to hydrogenate benzoylacetic acid derivatives with a high optical yield. Recently, an (R)-SEGPHOS/Ru complex-catalyzed hydrogenation of the ethyl ester with an S/C of 10,000 under 30 atm of H2 afforded the S alcohol in 97.6% ee (Table of Scheme 20) [36]. MeO-BIPHEP and Tol-P-Phos also performed with a high level of enantioselection [49, 60], Hydrogenation of N-methylbenzoylacetamide with the (R)-BINAP/Ru catalyst gave the S alcohol in >99.9% ee and 50% yield [61]. 

Experiments with tritium and C-labelled phenylalanine samples established that this amino-acid was incorporated intact as a Cg unit (with loss of C-1). Support for a pathway proceeding via cinnamic acid and hydroxylated derivatives and benzoylacetic acid derivatives was provided in further experiments with cinnamic acid, ferulic acid/isoferulic acid, and the (easily hydrolysed) ethyl esters of benzoylacetic acid and piperonylacetic acid. As far as they go the results suggest that a mixed pathway is in operation with introduction of hydroxy- and methylenedioxy-groups on more than one intermediate. 

Acetic acid amyl ester. See Amyl acetate Acetic acid, anhydride. See Acetic anhydride Acetic acid barium salt. See Barium acetate Acetic acid, benzoyl-, ethyl ester. See Ethyl benzoylacetate... 

Benzenepropanoic acid, p-oxo-, ethyl ester. See Ethyl benzoylacetate... 

Benzoxyline. See Benzoxiquine 1 -Benzoxy-1 -(2-methoxyethoxy)-ethane. See Benzyl methoxyethyl acetal Benzoxyquine. See Benzoxiquine Benzoyl acetic acid ethyl ester. See Ethyl benzoylacetate... 

The diazo compound from methyl benzoylacetate gives phenylcarbo-methoxyketene in 70% jdeld when the final decomposition is carried out in refluxing xylene, but it is converted largely to the ester of phenyl-malonic acid by heating in the absence of a solvent. The ethyl ester of ethylmalonic acid is the principal product from the decomposition (in the absence of a solvent) of the diazo compoimd obtained from ethyl pro-pionylacetate. A small amoimt of the ketene evidently was formed also. The diazo compound obtained from ethyl ethoxalylacetate on decomposition in warm xylene gives 54% of dicarbethoxyketene. ... 

Ethyl benzoylacetate has been prepared by the condensation (by means of sodium ethylate) of ethyl acetate with ethyl benzoate,1 acetophenone with ethyl carbonate,2 and acetophenone with ethyl oxalate, with subsequent heating 3 by treatment of ethyl phenylpropiolate4 or a-bromocinnamic acid 5 with concentrated sulfuric acid, and of ethyl diazoacetate with benzalde-hyde 6 by the condensation of benzene with the monoethyl ester of malonyl monoacid chloride and aluminum chloride,7 of benzoyl chloride with the product of the reaction of magnesium and ethyl chloroacetate in ether,8 of alcohol on benzoylacetimino ethyl... 

Benzotriazole, 20,16 Benzoylacetic ester, 23, 35 Benzoylation of acetoacetic ester by ethyl benzoate, 23, 35 Benzoyl chloride, 24, 14 purification of, 24, 15 Benzoyl Cyanide, 24,14, 16 Benzoyleormic acid, 24,16 Benzoyl-o-toluidines, conversion to indoles, 22, 95... 

The reaction mixture is cooled, 250 cc. of water is added, and mixture is made acid to litmus by addition of a cooled solu-koa of 100 g. of concentrated sulfuric acid in 200 cc. of water. Chipped ice is added if necessary to keep the mixture cool. The ui >er ester layer is separated, and the aqueous layer is extracted w% 200 cc. of ether. The combined ether and ester layers are ken with 350 cc. of a saturated sodium bicarbonate solution yr til no more carbon dioxide is evolved, and then the organic layer 1S fashed with 200 cc. of water. The water layer is combined with sodium bicarbonate solution and extracted with 400 cc. of e er. The combined ether and ester layers are dried over sodium Sl)lfate. The ether is removed by distillation on the steam bath, aiM the excess ethyl benzoate and acetoacetic ester (Note 3) are t removed by distillation under reduced pressure through a l tm. fractionating column. Finally, the ethyl benzoylacetate is tilled (Note 3) at 101-106°/1 mm. (130-135°/3 mm.). The y ld of ester boiling over a 5° range is 190-210 g. (50-55 per cent theoretical amount based on the ethyl acetoacetate). 

The reduction of other carbonyHc compounds such as 1,3-diketones or 3-oxo esters has also been extensively successfully described in the literature. In this manner, (R)-fluoxetine can be also synthesized through the bioreduction of ethyl benzoylacetate using Geotrichum sp. G38 that shows a complementary selectivity to the one shown by baker s yeast (Scheme 10.19) [47]. 

The cyano derivative of indandione 228 acting as an unsaturated nitrile reacts differently with 1,3-dicarbonyl compounds, depending on their nature (89CB1323). Acetylacetone and ethyl benzoylacetate provide spiro(indan-2,2 -pyrans) 229 acetoacetic esters give propellans 230 (proven by X-ray analysis). But only dimedone 103b among the ketones studied yields spirochromene 231 (Scheme 88). 

This general procedure is effective for the preparation of many types of phenylhydrazones. For example, a substituted diazo compound can be employed.2 Alkylated acetoacetic esters 8 and ethyl benzoylacetate 4 may be used. For the higher homologs, the a-formyl derivatives of ketones may be used in place of ethyl acetoacetate.6 6 Ethyl pyridylacetates may also be substituted for ethyl acetoacetate.7 The products in these cases are the phenylhydrazones of 2-acylpyridines. 

Acylation of the highly reactive indolizines may be achieved at the 3-position and, less easily, at the 1-position using acid chlorides, anhydrides and even esters (48CRV(42)6ll). 3-Acetylation of indolizine, 1,3-diacetylation of indole and 2,5-diacetylation of pyrrole have been effected with acetic anhydride at 140-200 °C (see Section 3.02.2.4.8 for details). The indolizines (49) and (50) are formed with ethyl chloroformate and ethyl benzoylacetate respectively. 

Aminopyridines were reacted with / -oxo esters, primarily ethyl acetoacetate and ethyl benzoylacetate, by heating above the melting point,33,37-38,42 49 occasionally in the presence of a few drops of hydro-... 

Ethyl benzoylacetate was hydrogenated with [RuCl2(p-cymene)]2, (S,R)-ephe-drine, and (CH3)2CHOK in 2-propanol to give the S hydroxy ester quantitatively in 94% ee (Scheme 32) [106]. Reduction of methyl 2-acetylbenzoate was performed with the 16-electron Ru catalyst, (S,S)-29 [72], in 2-propanol to afford (S)-3-methylphthalide in 97% ee and in 93% yield contaminated with 1% of 3-(2-isopropoxy)-3-methylphthalide (Scheme 33) [107]. 

Diaminopyrazoles 158 and 159 also react with /3-ketoesters in refluxing acetic acid (1-1.5 h) to give pyrazolo[l,5-A -l,2,4-triazepin-2-ones 160-163. Compounds 160-162 were prepared in 42—45% yield using the appropriate keto-esters, though ethyl benzoylacetate and ethyl pivaloylacetate failed to react, presumably by electronic and steric... 

The enamine (287 R3 = Bn, R1 + R2 = (CH2)20(CH2)2) reacts with ethyl benzoylacetate affording heterocycle (99) (87JHC111). Enamines (287 R3 = Me, R1, R2 = various groups) react with the ester (288) giving products (289) in moderate yield and related enamines behave similarly in this hetero-Diels-Alder reaction <85AP(318)648>. 

The acylation of simple /3-keto esters with acyl chlorides to form di-acylacetic esters proceeds readily however, the subsequent cleavage for removing the smaller acyl group is complicated in that the original keto ester may be regenerated. The optimum conditions for the conversion of benzoylacetoacetic ester to benzoylacetic ester with ammonium chloride and ammonium hydroxide have been studied. The over-all synthesis of this ester has been described (57%). An improved procedure for the ammonolysis of ethyl a-acetyl-/3-oxocaproate using gaseous ammonia has been described. By a similar process, a series of alicyclic /3-keto esters has been prepared in over-all yields of 20-40%. ... 

In the presence of sodamide the anionic form of 2-amino-l-ethylbenzimidazole is substituted by alkyl halides on both the annular and exocyclic nitrogens. With butyl and isopropyl iodides the proportion of dialkylated product is increased. The synthetic utility of such nucleophilic reactions of 2-aminobenzimidazole is exemplified by reactions with ethyl cyanoacetate, acetoacetic ester and ethyl benzoylacetate, when subsequent cyclization of the initial products also gives pyrimidobenzimidazole derivatives (Scheme 117). 

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