EduNinjaCompound R is a useful intermediate in the synthesis of pharmaceutical compounds. It can be made from compound P by the following route.
Suggest structures for the starting material P and the intermediate Q.
Suggest reagents and conditions for the following steps in the above scheme. step 1 step 2 step 4
Ethanolamine and phenylamine are two organic bases that are industrially important. Ethanolamine is a useful solvent with basic properties, whilst phenylamine is an important starting material in the manufacture of dyes and pharmaceuticals. The following table lists some of their properties, together with those of propylamine.
Apart from their relative basicities, ethanolamine and phenylamine differ in many of their reactions.
For each of these two compounds, describe one test that would give a positive result with the stated compound, but a negative result with the other.
ethanolamine
test
observation
phenylamine
test
observation
Suggest why bromination of phenol occurs more readily than bromination of benzene.
Phenolphthalein reacts separately with the two reagents shown in the table.
Complete the table by:
- drawing the structures of the organic products formed (part of the structure has been given for you)
- stating the types of reaction.
Methyl orange is another acid-base indicator. Its structure in aqueous solution at pH 4.4 is shown.
methyl orange
On the structure of methyl orange, circle the bond or bonds that make this compound a dye.
The colour of this indicator changes between pH 3.2 and pH 4.4 .
Describe and explain the relative acidities of phenol and ethanol.
Phenyl 2-hydroxybenzoate is an antiseptic.
phenyl 2-hydroxybenzoate
Complete the following table about the reactions of phenyl 2-hydroxybenzoate with the three reagents.
Suggest an explanation for the difference in the values of phenol and nitrophenol.
Noradrenaline is a hormone and neurotransmitter, which is released during stress to stimulate the heart and increase blood pressure.
noradrenaline
Dihydroxybenzaldehyde reacts with .
- Describe what you would see during this reaction.
- Draw the structure of the product.
Draw the structures of the products when noradrenaline is reacted with
dilute NaOH(aq),
dilute HCl(aq),
Compounds F and J are shown in Fig. 4.1.
Fig. 4.1
J reacts under suitable conditions with NaOH(aq).
After acidification of the reaction mixture, compounds K and L form.
Fig. 4.3
State the two types of reaction that occur when J reacts with NaOH(aq).
1
2
K can also be synthesised from phenol, .
Fig. 4.4 shows several reactions of phenol.
Fig. 4.4
Explain why phenol is a weaker acid than K.
Phenol and benzene both react with nitric acid, as shown in Fig. 4.5.
Fig. 4.5
Explain why the reagents and conditions for these two reactions are different.
Describe and explain how the acidities of ethanol and phenol compare to that of water.
Complete the following equations showing all the products of each of these reactions of phenol. Include reaction conditions where appropriate in the boxes over the arrows. If no reaction occurs write no reaction in the products box.
The analgesic drug paracetamol can be synthesised from phenol by the following route. Suggest reagents and conditions for the each of three steps, and suggest the structure of the intermediate H. Write your answers in the boxes provided.
Answer all questions in the spaces provided.
Methoxybenzene reacts with in a similar manner to phenol.
methoxybenzene
Suggest a chemical reaction you could use to distinguish between methoxybenzene and phenol. State the reagent, describe the observations you would make, and give an equation for the reaction.
reagent
observation
equation