Ethyl ethanoate, 659

Colourless, volatile liquid with a strong pearlike odour, b.p. 138-5 C. Manufactured by heating amyl alcohol (1-pentanol) with potassium ethanoate and sulphuric acid or by heating amyl alcohol with ethyl ethanoate in the presence of a little sulphuric acid. Commercial... 

Prepared by healing benzaldehyde with sodium ethanoate and ethanoic anhydride (Perkin reaction) or with ethyl ethanoate and sodium ethoxide. Occurs in storax, or liquid... 

Curtius transformation An alternative to the Hofmann transformation for obtaining an amine from an ester via the hydrazide, azide and isocyanate. Thus ethyl ethanoate is converted into melhylamine by the following series of reactions ... 

If copper is treated with a solution of dinitrogen tetroxide in ethyl ethanoate (acetate), a blue solution is obtained, which on evapora-... 

Chemical Designations - Synonyms Acetic acid, ethyl ester. Acetic ester. Acetic ether. Ethyl ethanoate Chemical Formula CHjCOOCHjCHj... 

Fig. 3.4a shows the chromatogram of some phthalates on a silica column using ethyl ethanoate/wo-octane 5 95 as the mobile phase. Some of the peaks are identified. "... 

You could first wash the column with methanol, then trichloromethane, then heptane (or methanol, ethyl ethanoate, heptane). You cannot go directly from methanol to heptane because the two are only partly miscible. The column needs to be washed with about 20 dead volumes of each solvent (about 50 cm3 of each solvent for a 25 cm x 4.6 mm column). To get back to CH3OH/H2O 50 50 you would have to go through the sequence of solvents in reverse. If buffer solutions or ion-pairing reagents have been used in the mobile phase, very much longer equilibration times may be needed. 

This is another reaction that involves carbanions derived from esters, e.g. (Ill), but this time adding to the carbonyl carbon atom of another ester molecule. The reason for considering it here rather than under carboxylic derivatives (p. 237) is that it can, in its initiation, be regarded as something of an analogue, for esters, of the aldol condensation on aldehydes (cf. p. 224), e.g. with ethyl ethanoate (acetate, 112) ... 

Prochiral imines can be hydrogenated to the corresponding amines with extremely high enan-tioselectivities in H20/ethyl ethanoate biphasic systems, using Rh1 complexes of sulfonated phosphines 342 The cationic rhodium complex [Rh(NBD)(131)]+ was an active catalyst for hydrogenation of 2-ethanamido-propenoic acid in aqueous solution.343... 

A quantity of ethyl ethanoate (A) is reacted with an excess of sodium hydroxide (BJ at 25 C. 100 cc of the reaction mixture required 68.2 cc of Of 0.05 mol/liter HC1 for neutralization at the beginning of the reaction. After 30 minutes, 100 cc of the mixture similarly required 49.7 cc of the acid, and when the reaction was complete, 100 cc of the mixture required 15.6 cc of the acid. The reaction is not reversible. Find the specific rate. 

SAQ 8.1 Consider the reaction between ethanoic acid and ethanol to form the pungent ester ethyl ethanoate and water ... 

Worked Example 8.2 Ethyl ethanoate (0.02 mol dm 3) hydrolyses during reaction with aqueous sodium hydroxide (0.1 moldm 3). If the rate of reaction is 3 x 102 moldm-3s-1, calculate the rate constant k. 

Each reaction has a unique value of rate constant k. For example, the value of k in Worked Example 8.2 would have been different if we had chosen ethyl formate, or ethyl propanoate, or ethyl butanoate, etc., rather than ethyl ethanoate. The value of k depends ultimately on the Gibbs function of forming reaction intermediates, as discussed below. 

But the reaction conditions are still more complicated because the stoichiometry of reaction might alter. Many greases and oils comprise the esters of long-chain fatty acids. The hydrolysing reaction between NaOH and an ester such as ethyl ethanoate proceeds with a stoichiometry of 1 1, but a tri-ester, such as most natural oils (e.g. olive oil or sunflower oil), occurs with a 1 3 stoichiometry, consuming one hydroxide ion per ester bond. Clearly, the hydroxide will be consumed more quickly when hydrolysing a triester than a mono-ester. The rate depends on the stoichiometry of reaction. 

In Investigation 1-A in Chapter 1, you carried out a condensation reaction to produce an ester called ethyl ethanoate. In this chapter, you learned about the reverse reaction hydrolysis. 

Synonyms Acetic ether Acetic acid, ethyl ester Acetidin Acetoxyethane AI3-00404 Caswell No. 429 BRN 0506104 CCRIS 6036 EINECS 205-500-4 EPA pesticide chemical code 044003 EtAc Ethyl acetic, ester Ethyl ethanoate FEMA No. 2414 NSC 70930 RCRA waste number U112 UN 1173 Vinegar naphtha. 

Senol, A. Vapor liquid equilibria of the systems ethyl ethanoate + 2-methyl-2-butanol, 2-methyl-l-propanol + 3-methyl-l-butanol, and cyclohexanol + benzyl alcohol at 101.32 kPa, J. Chem. Eng. Data, 43(5) 763-769, 1998. 

Let us now apply this rule to analyse the high resolution spectrum for ethyl ethanoate. O... 

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