Explain why trichloroethanoic acid, $\text{CCl}_3\text{COOH}$, has a higher acidity than ethanoic acid, $\text{CH}_3\text{COOH}$.
Acyl chlorides are made by reacting carboxylic acids with thionyl chloride, $\text{SOCl}_2$. Ethanedioyl chloride, $(\text{COCl})_2$, may be prepared by treating ethanedioic acid, $(\text{COOH})_2$, with an excess of $\text{SOCl}_2$. Write an equation for this reaction.
Separate samples of $(\text{COCl})_2$ are reacted with excess warm acidified $\text{KMnO}_4\text{(aq)}$ and with $\text{H}_2\text{NCH}_2\text{CH}_2\text{NH}_2$. The carbon-containing product from the reaction with $\text{H}_2\text{NCH}_2\text{CH}_2\text{NH}_2$ has molecular formula $\text{C}_4\text{H}_6\text{N}_2\text{O}_2$. Fill in the boxes in Fig. 9.1 to propose the structure of the carbon-containing product in each reaction.
A polyester can be produced by reacting $(\text{COCl})_2$ with ethane-1,2-diol, $\text{HOCH}_2\text{CH}_2\text{OH}$. Draw two repeat units of the polymer formed. Any functional groups should be shown.
Identify the yellow precipitate produced as $J$.
Complete Table 9.2 with the proton ($^1\text{H}$) NMR spectrum data for $H$, $\text{C}_6\text{H}_{10}\text{O}_3$.
Suggest a structure for $H$ that has formula $\text{C}_6\text{H}_{10}\text{O}_3$.