Esters ethyl formate

Esters Ethyl formate Propyl formate Methyl acetate Ethyl acetate Propyl acate Isopropyl acetate hco-o-c2h5 hco-o-c3h7 CH3-CO-0-CH3 ch3-co-o-c2h5 ch3-co-o-c3h7 CH3-C0-0-CH(CH3)2... 

F.2) Formic acid, ethyl ester, ethyl formate, ethyl methanoate 1109-94-4] FEMA 2434... 

Formic add elliyl ester [ethyl formate] see fruit esters. 

Ethylene Glycol Ethyl Formic Ester Ethyl Formate... 

As a general guide, however, it may be noted that the following have fairly easily recognisable odours methyl and ethyl formate methyl and ethyl acetate (apples) methyl and ethyl benzoate methyl salicylate (oil of winter-green) and ethyl salicylate methyl and ethyl cinnamate. (It is however usually impracticable to distinguish by odour alone between the methyl and ethyl esters of a particular acid.) Methyl and ethyl o. alate, and methyl and ethyl phthalate are almost odourless. Succinic and tartaric esters have faint odours. 

Ethyl oxalate is the only liquid ester which gives this rapid separation of the amide, which is therefore characteristic. Methyl and ethyl formate react rapidly with ammonia, but the soluble formamide does not separate methyl succinate gives crystalline succinamide after about I hour s standing, other esters only after a much longer time. The solid esters, other than methyl oxalate, are either soluble in water and remain so when treated with ammonia, or alternatively are insoluble in water and hence clearly not methyl oxalate. 

Freshly distilled ethyl formate must be used. Commercial ethyl formate may be purified as follows. Allow the ethyl formate to stand for 1 hour with 16 per cent, of its weight of anhydrous potassium carbonate with occasional shaking. Decant the ester into a dry flask containing a little fresh anhydrous potassium carbonate and allow to stand for a further hour. Filter into a di flask and distil through an efficient fractionating column, and collect the fraction, b.p. 53-54° protect the receiver from atmospheric moisture. 

Ethyl formate. Reflux a mixture of 61 g. (50 ml.) of A.R. formic acid (98/100 per cent.) and 31 g. (39-5 ml.) of absolute ethyl alcohol for 24 hours. Transfer to a Claisen flask with fractionating side arm (or attach a fractionating column to the flask), distil and collect the liquid passing over below 62°. Wash the distillate with saturated sodium bicarbonate solution and saturate with salt before removing the ester layer. Dry with anhydrous sodium or magnesium sulphate, filter, and distil. The ethyl formate passes over at 53-54°. The yield is 36 g. 

The benzoic acid derivative 457 is formed by the carbonylation of iodoben-zene in aqueous DMF (1 1) without using a phosphine ligand at room temperature and 1 atm[311]. As optimum conditions for the technical synthesis of the anthranilic acid derivative 458, it has been found that A-acetyl protection, which has a chelating effect, is important[312]. Phase-transfer catalysis is combined with the Pd-catalyzed carbonylation of halides[3l3]. Carbonylation of 1,1-dibromoalkenes in the presence of a phase-transfer catalyst gives the gem-inal dicarboxylic acid 459. Use of a polar solvent is important[314]. Interestingly, addition of trimethylsilyl chloride (2 equiv.) increased yield of the lactone 460 remarkabiy[3l5]. Formate esters as a CO source and NaOR are used for the carbonylation of aryl iodides under a nitrogen atmosphere without using CO[316]. Chlorobenzene coordinated by Cr(CO)j is carbonylated with ethyl formate[3l7]. 

Esters of high volatility, such as methyl formate, methyl acetate, and ethyl formate, have lower boiling points than those of the corresponding alcohols, and therefore can be readily removed from the reaction mixture by distillation. 

On digestion of this solid mass with 1 1. of ice and water, the sodium salt of the enol dissolves in the water, and the unreacted ester is removed by extracting the aqueous layer with two 200-ml. portions of ether (Note 5). The foimyl derivative settles out as an oil upon acidification of the aqueous layer with dilute sulfuric acid. The oil is extracted with three 200-ml. portions of ether, and the ethereal extract is washed several times with water and dried over anhydrous sodium sulfate. The ether is distilled, and, to remove traces of ethyl formate, the oil is heated on a steam bath under a pressure of 20-30 mm. for 1 hour. The remaining yellow formyl derivative weighs 27-29 g. (Note 6). 

Formate Esters Methyl formate Ethyl formate Propyl formate Isopropyl formate Butyl formate Isobutyl formate... 

Mixed Claisen condensations (Section 21.3) Diethyl carbonate, diethyl oxalate, ethyl formate, and benzoate esters cannot form ester enolates but can act as acylating agents toward other ester enolates. 

The mixed Claisen condensation of two different esters is similar to the mixed aldol condensation of two different aldehydes or ketones (Section 23.5). Mixed Claisen reactions are successful only when one of the two ester components has no a hydrogens and thus can t form an enolate ion. For example, ethyl benzoate and ethyl formate can t form enolate ions and thus can t serve as donors. They can, however, act as the electrophilic acceptor components in reactions with other ester anions to give mixed /3-keto ester products. 

Mixed Claisen-like reactions can also be carried out between an ester and a ketone, resulting in the synthesis of a jS-diketone. The reaction works best when the ester component has no a hydrogens and thus can t act as the nucleophilic donor. For example, ethyl formate gives high yields in mixed Claisen condensations with ketones. 

The common name of an ester consists of two words. The first word (methyl, ethyl,...) is derived from that of the alcohol the second word (formate, acetate,...) is the name of the acid with the -ic suffix replaced by -ate. Thus ethyl formate (Table 22.4) is made from ethyl alcohol and formic acid ... 

Ethyl formate Formic acid, ethyl ester (8, 9) (109-94-4) Tetrabutylammonium hydrogen sulfate Ammonium, tetrabutyl-, sulfate (1 1) (8) 1-Butanaminium, N,N,N-tributyl-, sulfate (1 1) (9) (32503-27-8)... 

The mechanism of the condensation in Part D probably involves thioformylation of the metallated isocyanoacetate followed by intramolecular 1,1-addition of the tautomeric enethiol to the isonitrile. This thi2izole synthesis is analogous to the formation of oxazoles from acylation of metallated isonitriles with acid chlorides or anhydrides. " Interestingly, ethyl formate does not react with isocyanoacetate under the conditions of this procedure. Ethyl and methyl isocyanoacetate have been prepared in a similar manner by dehydration of the corresponding N-formylglycine esters with phosgene and trichloromethyl chloroformate, respectively. The phosphoryl chloride method described here was provided to the submitters by Professor U. Schollkopf and is based on the procedure of Bohme and Fuchs. The preparation of O-ethyl thioformate in Part C was developed from a report by Ohno, Koi/.uma, and Tsuchihaski. " ... 

Intermediate species concentrations in fuel-rich flames (C/O = 0.5) of the two isomeric esters methyl acetate (left) and ethyl formate (right) burnt under identical conditions mole fraction, h height species named on the left side of each graph correspond to left y-axes, species on the right to right y-axes. 

Ofiwald, P. et al.. Isomer-specific fuel destruction pathways in rich flames of methyl acetate and ethyl formate and consequences for the combustion chemistry of esters, /. Phys. Chem. A, 111, 4093,2007. 

Ethonam (99), an imidazole derivative with a very different substitution pattern, is also reported to possess antifungal activity. To prepare it, alkylation of aminotetralin 94 with methylchloro-acetate gives the glycine derivative 95. Heating with formic acid then affords the amide 96 this compound is then reacted with ethyl formate to yield hydroxymethylene ester 97. Reaction with isothio-cyanic acid gives the imidazole-2-thiol 98. (The... 

The lower spectrum shows an ester group (triplet at 1.2 ppm, quartet at 4.2 ppm) and a singlet at 8.1 ppm, the latter indicating the presence of a formyl group. Peak 1 results from ethyl formate, formed by adventitious hydrolysis of the acetal 4. The middle and top spectra correspond to the two acetals (see equation) the assignment is very simple. 

The crude product of reaction of methanol and carbon monoxide at 100°C/70 bar in presence of 0.5% of sodium methoxide was discharged after cooling into a storage bottle, which burst 4 h later. This was attributed to extreme instability of the ester in presence of the base, leading to the reverse reaction with vigorous evolution of carbon monoxide. Immediate neutralisation of the reaction mixture would prevent the decomposition, which also occurs with ethyl formate and base. See Other GAS EVOLUTION INCIDENTS... 

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