EduNinjaDiesters can be made from diacids such as propane-1,3-dioic acid, .
Which combination of reactants would form the diester ?
butane-1,4-dioic acid and ethanol
ethanedioic acid and propan-1-ol
ethanedioic acid, ethanol and butan-1-ol
propane-1,3-dioic acid, ethanol and propan-1-ol
Compound G is a naturally occurring aromatic compound that is present in raspberries.
compound G
Suggest a reaction scheme by which compound G and propanoic acid could be converted into compound L.
Answer all the questions in the spaces provided.
Compounds F and J are shown in Fig. 4.1.
Fig. 4.1
K can also be synthesised from phenol, .
Fig. 4.4 shows several reactions of phenol.
Fig. 4.4
Write an equation for the formation of M in reaction 1 .
Draw N, the product of reaction 2 .
Esterases are enzymes that hydrolyse esters.
Enzymes can be quite specific in the structures of the substrates they act upon. For example, an esterase isolated from the mould Aspergillus niger will hydrolyse phenyl ethanoate, , but not its isomer methyl benzoate, .
Sample bottles of each of the isomers phenyl ethanoate and methyl benzoate have lost their labels and so have been named isomer A and isomer B.
These two isomers are difficult to distinguish chemically.
Describe a method of converting them to suitable products in step 1 which can then be tested in step 2.
You should state the reagents and conditions for each step, and any observations you would make.
step 1
step 2
P can be used to make compound Q in a single step reaction.
Give the structural formula of the compound that is added to P to make Q and give the formula of the other product of this reaction.
compound added to P
other product
When an ester is treated with in dry ether the ester linkage is cleaved by the addition of four hydrogen atoms and two alcohols are produced.
Draw the structures of the compounds formed when Q is treated with an excess of in dry ether.
Compound T is made by a three-stage synthesis.
In stage 1, phenylethanoic acid reacts with a suitable reagent to form compound R.
stage 1
phenylethanoic acid
Suggest a suitable reagent for stage 1.
Acebutolol is a drug that can be used to lower blood pressure.
acebutolol
On warming with dilute hydrochloric acid, acebutolol splits to form two molecules.
Draw a line through the bond broken by heating with dilute hydrochloric acid.
Draw the structure of the smaller molecule produced by this reaction.
Two molecules of compound F react together under suitable conditions to form compound G. Some information about compounds F and G is given.
- The mass spectrum of F has a peak due to the molecular ion at m / e=106, and a peak at m / e=107 with an abundance 8 % of the 106 peak.
- The mass spectrum of G has a peak due to the molecular ion at m / e=212, and major peaks at m / e=91 and m / e=105.
- Both F and G contain oxygen and are neutral compounds which are insoluble in water.
- The NMR spectrum of F includes a singlet peak at due to one proton.
- The NMR spectrum of G includes a singlet peak at due to two protons.
- When G is heated with dilute sulfuric acid, benzoic acid, , and phenylmethanol, , are produced.
Use this information to answer (i)-(vi).
State the type of reaction that G undergoes when heated with dilute sulfuric acid.
The ester 4-methylphenyl benzoate is used in the manufacture of perfumes.
4-methylphenyl benzoate
Suggest a two-step route for the synthesis of 4-methylphenyl benzoate from 4-methylphenol and benzoic acid.
Include reagents and conditions for each step, and the structure of the intermediate compound.
Tyrosine and lysine, shown in Fig. 9.1, are naturally occurring amino acids found in proteins.
Fig. 9.1
When ethanoic acid is treated with product D is formed.
When D is added to tyrosine two different isomeric products, E and F, are formed.
E has an ester linkage, F does not.
Draw the structures of D, E and F in the boxes below.
D