What's in a Medicine 13.5 Esters 4.5 / 5 based on 2 ratings ? ChemistryAcids, bases and saltsFunctional GroupsA2/A-levelSQA Created by: EmilyCreated on: 15-01-13 10:42 Alcohol + carboxylic acid…? Also give conditions Ester + water. Heated under reflux with conc H2SO4 or HCl 1 of 18 What is esterification? Establishment of the ester link. Condensation of hydroxyl in alcohol and carboxyl in acid 2 of 18 What is aesthetically noted about esters? Strong sweet odour often floral/fruity 3 of 18 Why are esters also widely used as solvents? Many organic compounds dissolve readily in them 4 of 18 Draw and name CH3CH2OCOCH3 Ethyl ethanoate. –O is ethyl, =O ethanoate 5 of 18 Polyesters are ____________ polymers Condensation 6 of 18 How are they made? From reacting a diol and a dicarboxylic acid 7 of 18 What is a phenol? Benzene ring + OH 8 of 18 When forming an ester from a phenol, why is a vigorous reagent required to esterify it? The OH group in phenol is less reactive 9 of 18 When ethanoic acid is involved in esterification, the process is sometimes called… Ethanoylation 10 of 18 Ester = phenol + ? Acyl chloride/acid anhydride 11 of 18 Describe briefly how to make an ester from a phenol Phenol treated with acyl chloride/acid anhydride. With AA, mixture heated under reflux/With AC, mixture at rm tmp. 12 of 18 Making an ester from a phenol must be carried out in the absence of… Water 13 of 18 What is the reverse of esterification? Ester hydrolysis 14 of 18 Ester + water = Alcohol + carboxylic acid 15 of 18 The reaction is very slow… what do we do? (Example) Add a catalyst! Dilute sulfuric acid used usually 16 of 18 Ester + alkali = Alcohol + carboxylate salt 17 of 18 What is the difference between the two above reactions (minus the reagents) Alkaline hydrolysis goes to completion unlike acid hydrolysis – usually preferred 18 of 18
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