Purification, general procedures esters

Purification of the solution after coulometric reduction (which took 4e per molecule) followed by oxidation (1.5e recovered) resulted in a 70% yield of isolated C70. It thus appears as if the retro-Bingel reaction is a general procedure to remove ester-substituted methano-adducts from fullerenes. 

The procedure described below is quite general and uses finely, freshly machine--powdered KOH, which is added to a solution of the primary or secondary (acetylenic) alcohol and a 10-15% molar excess of tosyl chloride in Et20, kept around 0 C The excess of tosyl chloride is destroyed during the reaction of the excess of KOH. Side- and subsequent reactions ("saponification of the ester by KOH and 1,2-elimination of p-toluenesulfonic acid from thtfester) can be suppressed by keeping the temperature of the reaction mixture below 5 C. This procedure can be carried out within 2 h and generally gives excellent (often almost quantitative) yields of the tosylates. Purification of acetylenic tosylates by distillation, which is risky because of the limited thermal stability of the esters, is not necessary because the... 

When treated with concentrated alkali, acetoacetic ester is converted into two moles of sodium acetate, (a) Outline all steps in a likely mechanism for this reaction. (Hint See Sec. 21.11 and Problem 5.8, p. 170.) (b) Substituted acetoacetic esters also undergo this reaction. Outline the steps in a general synthetic route from acetoacetic ester to carboxylic acids, (c) Outline the steps in the synthesis of 2-hexanone via acetoacetic ester. What acids will be formed as by-products Outline a procedure for purification of the desired ketone. (Remember that the alkylation is carried out in alcohol that NaBr is formed that aqueous base is used for hydrolysis and that ethyl alcohol is a product of the hydrolysis.)... 

Fatty acids, soaps and fatty acid methyl esters are the most extensively used oleochemicals [13]. The free fatty acids are prepared by hydrolysis of oils and fats by alkalis. This procedure named saponification proceeds at high temperature and pressure and leads to crude soaps the acidification of which gives fatty acids. They are subjected to various purification procedures, and finally isolated individually or as mixtures of carboxylic acids of the general formula RCOOH or as soaps RCOOM. The carboxylic acid methyl esters can be produced in two ways by esterification of the isolated carboxylic acid with methanol or by low-temperature... 

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