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The volatile compounds of three Langjiu (&ldquo, Honghualangshi, HHL&rdquo, &ldquo, Zhenpinlang, ZPL&rdquo, and &ldquo, Langpailangjiu, LPLJ&rdquo, ) were studied by gas chromatography-olfactometry (GC-O) and gas chromatography-mass spectrometry (GC-MS). The results showed that a total of 31, 30, and 30 ester compounds making a contribution to aroma were present in the HHL, ZPL, and LPLJ samples, respectively. From these esters, 16 compounds were identified as important odour substances, and their odour activity values (OAVs) were greater than 1. The key ester components were selected as: ethyl acetate, ethyl 2-methylbutyrate, ethyl 3-methyl butyrate, ethyl hexanoate, and ethyl phenylacetate by aroma extract dilution analysis (AEDA), odour activity value (OAV), and omission testing. Five esters were studied for perceptual interactions while using Feller&rsquo, s additive model, OAV, and a vector model. Among these mixtures, they all have an enhancing or synergistic effect. Among these mixtures, one mixture presented an additive effect and nine mixtures showed a synergistic effect.

In this work, a total of 35 important aroma compounds with odor activity values (OAVs) greater than 1 were detected by gas chromatography–mass spectrometry (GC–MS) in traditional Chinese-type soy sauce. Of these, fragrant compounds with aromatic rings (20 compounds) accounted for a large proportion, over 57%. Combining principal component analysis and GC–olfactometry–MS (GC–O–MS), 5-methyl-2-furanmethanethiol (OAV: 284–467), 3-methylbutanal (OAV: 409–938), phenylacetaldehyde (OAV: 47.4–566), 2–phenylethanol (OAV: 7.41–14.3), phenylethyl acetate (OAV: 7.00–18.1) and ethyl phenylacetate (OAV: 12.7–21.3) were confirmed as the typical fragrant compounds among all samples. Furthermore, full two-dimensional gas mass spectrometry (GC × GC–TQMS) was applied and 414 aroma compounds were identified, which included another 85 fragrant compounds with aromatic rings.

Authenticity and the geographical origin of wines are terms of great importance for consumers and producers. This work is focused on distinguishing between red wines from Poland and from other European countries, notably France, Italy and Spain. To achieve this goal, we determined aroma compounds in wines from different countries by headspace solid-phase microextraction/gas chromatography-mass spectrometry. The content of hexan-1-ol in Polish wines was significantly higher (about twice as high) than in French, Italian and Spanish wines. Linear discriminant analysis (LDA) showed that 3-(methylsulfanyl) propane-1-ol, hexan-1-ol, ethyl phenylacetate and ethyl 2-hydroxy-4-methylpentanoate were the most discriminant variables for distinguishing between wines from Poland and from other European countries. Hierarchical cluster analysis (HCA) revealed that Polish wines were separated thoroughly from the other wines based on ethyl phenylacetate, hexan-1-ol, ethyl 2-hydroxy-4-methylpentanoate, (E)-3-hexen-1-ol, 2-phenylethanol and 3-(methylsulfanyl)propan-1-ol, which is important for preventing possible frauds.

Backgrounds and Aims: This study aimed to determine a consumer rejection threshold (CRT) for ethyl phenylacetate (EPhA) and phenylacetic acid (PhAA) in wine. These compounds have recently been reported to be responsible for sweet-like, honey off odours in wine made from sour rotten grapes. Methods and Results: Non-expert wine consumers (n = 35) received pairs of samples comprising a control wine against a spiked wine with an ascending concentration of the target compounds and were asked to indicate which sample they preferred. Results estimated a conjoint CRT for EPhA and PhAA of 140 and 700 mg/L, respectively. Wines spiked with a EPhA and PhAA concentration around the CRT evoked intense ‘dried fruit’ aromas that led to a decrease of the general aroma quality; these wines are significantly rejected by consumers. Conclusions: The measured CRT provides an initial estimation of the risk concentration for EPhA and PhAA in red wine, as they represent a ‘taint’ for regular wine consumers. Significance of the Study: These data allow wine producers to predict if a given wine will be disliked by consumers or to help guide ‘blending away’ of such wines.

This study evaluates the specific impact of isolated yeast strains on the aromatic profile of fermented musts from Prieto Picudo, an autochthonous Castilla y León (Spain) red grape variety with an increasing demand in the local marketplace. For this purpose, the aroma profiles of wines elaborated from Prieto Picudo grapes have been studied by sensory analysis, gas chromatography-olfactometry (GC-O) and gas chromatography-mass spectrometry (GC-MS), with the aim of determining the potential of each strain to generate distinctive varietal and fermentation-derived aromatic compounds. The results have shown that the yeast strain exerts a critical influence on the levels of some fermentative (linear and branched ethyl esters, fatty acids, ethyl phenylacetate) and varietal compounds (4-mercapto-4-methyl-2-pentanone, 3-mercaptohexylacetate, β-damascenone), thus inducing a deep influence on the final aroma of the wine. Combination of both sensory and chemical data arises as a major tool to monitor the different patterns of aroma release and formation from selected yeast strains during the winemaking process.

Ethyl phenylacetate can be widely applied in many industries, such as food, medicines, cosmet- ics and medicinal herbs. At the moment, the production of natural ethyl phenylacetate is very limited. However, the biotransformation production of natural ethyl phenylacetate has an very extensive application prospect. This paper is written by taking the phenylacetic acid tolerance and the esterifying enzyme activity as the two indexes for screening the HA14 strain of hansenula anomala mutagenic which is regarded as the microorganism of ethyl phenylacetate production through biotransformation. By optimizing the production condition of phenylacetic acid and the esterification condition of ethyl phenylacetate, the production of ethyl phenylacetate accomplished through biotransformation within 72 hours can reach 864mg/L which is 171% of that of the initial bacterial strain.

Carboxylic esters were reduced to alcohols by diphenylsilane catalyzed by a Rh complex at room temperature. For example, ethyl decanoate and ethyl phenylacetate were converted to decanol and 2-phenylethanol by [ RhCl(cod) ] 2 4PPh 3 for 72 hours in 98 and 92% yields, respectively. Wilkinson's catalyst is also usable, and the reduction of ethyl decanoate finished in 6 hours at room temperature. The bromo-substitutent on ethyl 7-bromoheptanoate remained intact through this reduction.

The condensation of ethyl phenylacetate or ethyl β-hydroxybutyrate with Schiff bases in presence of an excess of lithium diisopropylamide or lithium hexamethyldisilazide leads to unsaturated amines instead of the expected β-lactams

Carboxylic esters were reduced to alcohols by diphenylsilane catalyzed by a Rh complex at room temperature. For example, ethyl decanoate and ethyl phenylacetate were converted to decanol and 2-phenylethanol by [ RhCl(cod) ] 2 4PPh 3 for 72 hours in 98 and 92% yields, respectively. Wilkinson's catalyst is also usable, and the reduction of ethyl decanoate finished in 6 hours at room temperature. The bromo-substitutent on ethyl 7-bromoheptanoate remained intact through this reduction.

Single-walled nanotubes (SWNTs) suspended in chlorobenzene (PhCl) and ethyl phenylacetate (EPA) were incorporated into microcapsules using an in situemulsification polymerization of urea-formaldehyde; the capsules release the SWNTs upon mechanical rupture.

4-Phenyl-3-oxobutanenitrile is synthesized via the reaction of ethyl phenylacetate with acetonitrile in the presence of sodium hydride and identified by isolating its 2-phenylhydrazone and dimethylaminomethylidene derivatives; both the hydrazone and dimethylaminomethylidene derivatives prove versatile starting materials for the synthesis of a variety of polyfunctionally substituted heterocycles.

An experiment involving the Claisen condensation reaction for a first-year organic chemistry laboratory is presented. Claisen condensations are routinely covered in organic textbooks but owing to the long reaction times required to reach equilibrium in solution they are seldom explored in the undergraduate teaching laboratory. In this experiment, potassium tert-butoxide and ethyl phenylacetate are heated to 100 °C for 30 minutes under solvent-free conditions to produce 2,4-diphenyl acetoacetate in 80% yield. The solvent-free nature of this procedure greatly reduces the quantity of waste generated by students relative to typical carbonyl condensation experiments.

The condensation of ethyl phenylacetate or ethyl β-hydroxybutyrate with Schiff bases in presence of an excess of lithium diisopropylamide or lithium hexamethyldisilazide leads to unsaturated amines instead of the expected β-lactams

The major component of the trail pheromone of the South American leaf-cutting ant,Atta sexdens rubropilosa Forel, is 3-ethyl-2,5-dimethylpyrazine (II). Methyl and ethyl phenylacetate and methyl 4-methylpyrrole-2-carboxylate (I), which is the major component of the trail pheromone ofA. texana (Buckley) andA. cephalotes (L.), were also identified and may be minor components. The pheromone is stored in the poison gland.Atta sexdens sexdens (L.) also responds strongly to the pyrazine, which in large amounts evokes a weak response fromA. texana, A. cephalotes, andAcromyrmex octospinosus (Reich). Foraging workers ofAtta sexdens rubropilosa did not preferentially pick up baits impregnated with the pyrazine. The pyrazine was puffed into the nests ofA. cephalotes, and a particular response called “milling” was noted.

Allenes (CF 3 ) 2 CCC(COOMe) 2 and (CF 3 ) 2 CCC(COOEt) Ph were prepared by Cs-catalyzed condensation of octafluoroisobutene with dimethyl malonate and ethyl phenylacetate respectively. A stable salt is formed from (CF 3 ) 2 CCC(COOMe) 2 and CsF. Similar salts were prepared through the condensation of octafluoroisobutene with ethyl cyanoacetate and malononitrile. Allenes (CF 3 ) 2 CCOMe 2 and (CF 3 ) 2 CCCHPh were synthesized by dehydrofluorination of olefines (CF 3 ) 2 CHCFCRR′ under the action of octafluoroisobutene and CsF mixture; the latter allene has been isolated only as a cycloadduct with octafluoroisobutene.

Manche elektrolytisch reduzierbaren organischen Verbindungen – die wir „Probasen” (PB) nennen mochten – bilden bei kathodischer Reduktion negativ geladene Zwischenprodukte, die fahig sind schwache CH-Sauren (RH) zu deprotonieren. Die enstandenen Carbanionen R⊖ konnen dann an verschiedenen in-situ-Folgereaktionen teilnehmen. Unter geeigneten Bedingungen konnen die „Probasen” auch wieder zuruckgebildet werden. Die Probleme um in sich widerspruchsfreie Reaktionsschemas aufzustellen, werden diskutiert. Es wird z. B. gezeigt wie Azobenzole 4 oder Tetraalkyl(ethentetracarboxylate) 5 als „Probasen” in Gegenwart von Ethyl(phenylacetat) (6a) oder 9-Phenylfluoren (7a) als schwache CH-Sauren reagieren und in situ eine Carboxylierung mit CO2 als Folgereaktion eingehen. Synthetic Utilization of Electrogenerated Bases, III. — Elektrocarboxylation, III. — Carboxylation of Weak CH-Acids1 Certain electroreducible organic compounds – named „probases” (PB) – cathodically form negatively charged species capable of deprotonating weak CH-acids (RH) to carbanions R⊖ which may then engage in various in situ follow-up reactions. Under appropriate conditions the „probases” may also be regenerated. The problems met in devising internally compatible reaction schemes are discussed. It is demonstrated, e. g., how the azobenzenes 4 or the tetraalkyl ethenetetracarboxylates 5 react as „probases” in presence of ethyl phenylacetate (6a) or 9-phenylfluorene (7a) as CH-acids and undergo carboxylation in situ with CO2 as follow-up reactions.

Reactions of 3-aryl-1-phenyl-2-propen-1-ones IIa-d with ethyl phenylacetate (I) in the presence of sodium ethoxide under reflux for one hour gave only the corresponding 3,5-diaryl-2,4-dibenzoyl-6-phenyl-cyclo-hexanones IIIa-d. The reaction of these compounds with hydrazine hydrate afforded the corresponding 5-benzoyl-4,6-diaryl-3,7-diphenyl-1,4,5,6,7-pentahydro-1H-indazole IVa-d. The structures of the products were established by spectroscopic (ir, uv, nmr and mass spectra), single-crystal X-ray analysis and chemical evidence.

3-Aryl-1-phenyl-2-propen-1-one I reacted with ethyl phenylacetate (II) in the presence sodium ethoxide at room temperature to give the corresponding ethyl β-aryl-γ-benzoyl-α-phenyl-butyrate III. However,' when the same ketones were refluxed with ethyl phenylacetate, they gave the corresponding 4-aryI-3,6-diphenyl-3,4-dihydro-2H-pyran-2-ones IV. The reactions of III and IV with hydrazine hydrate afforded the corresponding hydrazones VI and 2-pyridones VIII, respectively. The structure and configuration of the products are based on chemical and spectroscopic evidence.

1, 3-Diaryl-2-propen-1-ones (IIa, b) reacted with methyl α-naphthylacetate (Ib) in the presence of sodium methoxide at room temperature, or under reflux to give only the corresponding 4, 6-diaryl-3-[3^-(1^-3^-diarylpropan-1^-one)]-3-α-naphthyl-4-hydro-2H-pyran-2-ones (IIIa, b). However, on reacting the ketones (IIc-f) with ethyl phenylacetate (Ia) in the presence of sodium ethoxide at room temperature, or under reflux, the corresponding ethyl γ-aroyl-β-aryl-α-phenyl-butyrates (IVa-d) or 4, 6-diaryl-3-[3^-(1^-, 3^-diarylpropan-1^-one)]-3-phenyl-4-hydro-2H-pyran-2-ones (IIIc, d), respectively, were obtained. The reaction of these compounds, (III) and (IV), with hydrazine hydrate gave the corresponding (3H)-1, 2-diazepin-3-one (VI) and hydrazone (IX) derivatives, respectively. The structures of the products were established by chemical and spectroscopic evidence.

Aroylphenylacetylenes reacted with ethyl phenylacetate and benzyl cyanide in the presence of sodium ethoxide to give 6-aryl-3,4-diphenyl-2H-pyran-2-ones (2) and 4-aroyl-2,3-cis-diphenyl-crotonitriles (11), respectively. The structure and configuration of the products are based on chemical and spectroscopic evidence.

Electrochemical oxidation of lithium enolates of esters containing no activating groups at low temperature produced the corresponding substituted succinate esters in fairly good yields Electrolysis of enolate of ethyl phenylacetate also produced a quantitative yield of the oxidative dimer with 100% current efficiency.

Photochemical ethoxycarbonylmethylation of benzene with ethyl haloacetate has been studied in the presence of SbCl 5 , AlCl 3 , ZnCl 2 or FeCl 3 . In all cases, ethyl phenylacetate (2·3–24·4%) was obtained as a sole photoproduct and diethyl succinate, which suggests the formation of an ethoxycarbonylmethyl radical, could not be detected. The similar reaction of toluene in the presence of ZnCl 2 gives ethyl p -tolylacetate (12·8%) without o - and m -isomers. A probable reaction pathway involving photochemical electrophilic substitution is discussed.

The ultraviolet light-induced reaction of ethyl haloacetate with an excess benzene gives ethyl phenylacetate (1.7%) and diethyl succinate (1.6%) as main products, while the same reaction of excess chloroacetate with benzene gives ethyl phenylacetate higher yield (optimum 78.4%). Addition of aluminum chloride to the reaction mixture using an excess benzene gives ethyl phenylacetate as a sole product (11.5%). The effect of reaction conditions on the yield is examined.

Attempted condensation of dimethylacetamide diethylacetal (Ia) with ethyl phenylacetate (IV) was unsuccessful whereas the reaction of N, N-dimethylvinylamine (IIa) with IV afforded crotonic acid derivative (V) (type A reaction). On the other hand, intramolecular condensation between amide acetals with ester carbonyl (type B reaction) was found to proceed smoothly. Thus, the enamino ketone derivatives (Xa, b) were obtained from the amide acetals (IXa, b) by simply refluxing them in t-butanol.

1-Phenylazulene (I) and 2-phenylazulene (II) were synthesized from the troponoid compound. 3-Phenyl-(III) and 3-benzoyl-2H-cyclohepta[b]furan-2-ones (IV) were prepared by the reaction of 2-chlorotropone with ethyl phenylacetate and with ethyl benzoylacetate respectively. The reactions of III with malononitrile or ethyl cyanoacetate gave 1-phenylazulene derivatives, from which I was derived. On the other hand, the reactions of IV with ethyl cyanoacetate or diethyl malonate gave 2-phenylazulene derivatives, from which II was derived.

Electrochemical oxidation of lithium enolates of esters containing no activating groups at low temperature produced the corresponding substituted succinate esters in fairly good yields Electrolysis of enolate of ethyl phenylacetate also produced a quantitative yield of the oxidative dimer with 100% current efficiency.

1, 3-Diaryl-2-propen-1-ones (IIa, b) reacted with methyl α-naphthylacetate (Ib) in the presence of sodium methoxide at room temperature, or under reflux to give only the corresponding 4, 6-diaryl-3-[3^-(1^-3^-diarylpropan-1^-one)]-3-α-naphthyl-4-hydro-2H-pyran-2-ones (IIIa, b). However, on reacting the ketones (IIc-f) with ethyl phenylacetate (Ia) in the presence of sodium ethoxide at room temperature, or under reflux, the corresponding ethyl γ-aroyl-β-aryl-α-phenyl-butyrates (IVa-d) or 4, 6-diaryl-3-[3^-(1^-, 3^-diarylpropan-1^-one)]-3-phenyl-4-hydro-2H-pyran-2-ones (IIIc, d), respectively, were obtained. The reaction of these compounds, (III) and (IV), with hydrazine hydrate gave the corresponding (3H)-1, 2-diazepin-3-one (VI) and hydrazone (IX) derivatives, respectively. The structures of the products were established by chemical and spectroscopic evidence.

9-Bromobenzosuberone was converted via 9-cyanobenzosuberone into several other 9-substituted benzosuberones, but attempts to cause them to cyclise to the tricyclic 1,4-ethano-3-benzazepine ring system were unsuccessful. Both ethyl phenylacetate and ethyl 3-methoxyphenylacetate were converted by conventional procedures into the corresponding 6,7,8,9-tetrahydro-5-methyl-9,10-dioxo-5,8-methano-5H-benzocycloheptenes. The 3-methoxy derivative was further converted into N-benzyl-8-bromo-6,7,8,9-tetrahydro-3-methoxy-5-methyl-9-oxo-5H-benzocycloheptene-5-carboxamide which could be converted into the tricyclic 3-benzyl-2,3,4,5-tetrahydro-8-methoxy-1-methyl-2,5-dioxo-1,4-ethano-1H-3-benzazepine and thence in two steps into both 3-benzyl-2,3,4,5-tetrahydro-8-methoxy-1-methyl-1,4-ethano-1H-3-benzazepine and 3-benzyl-2,3,4,5-tetrahydro-8-hydroxy-1-methyl-1,4-ethano-1H-3-benzazepine. Also prepared were 3-benzyl-2,3,4,5-tetrahydro-5-hydroxy-8-methoxy-1-methyl-1,4-ethano-1H-3-benzazepine and 3-benzyl-3,4-dihydro-8-methoxy-1-methyl-1,4-ethano-1H-3-benzazepin-5(2H)-one.

Treatment of benzyl methyl ether with n-butyl-lithium–tetramethylenediamine in hexane gave benzylic-lithiation, without ortho-lithiation or a Wittig type rearrangement. The benzylic-lithiated benzyl methyl ether was then allowed to react with benzophenone, 4-methoxybenzophenone, butyl bromide, ethyl phenylacetate, and 4-chlorobenzophenone.