Organic Chemistry Alternative Exam

 

Introduction

Esters are chemicals that commonly have very strong sweet smell. Both the pharmaceutical and food industries use esters to enhance the flavours and fragrances of various products (if you have ever eaten Pear Drops then you almost certainly have eaten an ester!!).

Aim

You are working in Bellerbys Ice-Cream Factory and have been asked to produce a new Strawberry flavour called methyl trans cinnamate.  The chemical structure is given below.

 

Your task

TASK 1

The laboratory has provided you with the following chemicals and equipment:

Methane
Prop-2-en-1-ol
Standard lab chemicals and equipment

Your job is to produce a report to show how you could produce methyl propenoate from methane and prop-2-en-1-ol. Clue: To make methanol from methane will take two steps.

The use of esters has for a long time been used in industrial chemistry. It has been defined as a chemical compound that is gotten from either organic or inorganic acid which as a minimum, one hydroxyl group is eliminated and its place taken by an alkyl

TASK 2

Another strawberry ester has a similar structure to methyl trans cinnamate, but the manager wants you to make a sample of phenyl ethyl methanoate to compare the taste and smell.

You are provided with:

Methanoic acid
Ethene
Standard laboratory equipment

 

 

In your report explain how you would make the ester ethyl methanoate.

 

TASK 3

Using your ester produced in part 2 and benzene, show how you would produce a sample of phenyl ethyl methanoate.

The process begins with nitration of benzene. This is done in the presence of a mixture of water, nitric acid and sulphuric acid. This is sometimes referred to as a “mixed acid”. The process is mostly dangerous due to its exothermic nature i.e. ΔH = −117 kJ/mol.

In your report you should include:

IUPAC names of the products at each stage
Geometric isomerism
Mechanisms
Balanced chemical equations
Observations for functional group tests
Structure of benzene
Produce a detailed synthesis map showing all names, structures and reaction conditions, such as catalyst and temperature
References using Harvard referencing style.

 

Success Criteria (Part 1)

Marking points
No of marks
Achieved

Use of correct IUPAC names

Geometric isomers

5
 

Use a combination of displayed, structural and displayed formulae
5
 

Provide possible mechanisms:

(a)       Free radical substitution

(b)       Electrophilic addition

(c)       Electrophilic substitution

(d)       Nucleophilic substitution

(e)       Nucleophilic addition

(f)        Oxidation

 

***ALL REACTION MECHANISMS MUST BE HAND DRAWN ACCURATLEY.

COPY AND PASTE IS NOT ACCEPTABLE***

10
 

Reagents and conditions required for each reaction (can be marked from the synthesis map)
5
 

Observations of functional group tests
5
 

Structure of benzene
5
 

References
5