Question

pls answer 1-4 I would like to check with my answer

1) Saponification of triglycerides gives glycerol and fatty acid salts as shown in the equation below. The groups R1, R2 and R3 represent hydrocarbon chains that may be the same or different.

Saponification is actually a hydrolysis reaction. Explain what a hydrolysis reaction is and the role of sodium hydroxide in this process.

2)The over-the-counter drug Ibuprofen is a 1:1 mixture of R and S isomers of the compound 2-(4-isobutylphenyl)propanoic acid. The two compounds have identical physical properties, but only the S isomer has drug activity. Explain the structural difference between these isomers that accounts for these observations.

3) Halogenation of alkanes in the presence of light is an example of an organic reaction that occurs via free radical intermediates.One example of this is the reaction between methane and chlorine shown in the equations below. Free radical reactions occur in a series of steps called Initiation, Propagation and Termination. Write equations to show an example of each of these steps in the reaction of methane with chlorine in the presence of light.

Initiation reaction (1 mark)

Propagation reaction (1 mark)

Termination reaction (1 mark)

4) The preparation of ethoxybenzene from the reaction between sodium phenoxide and bromoethane is shown in the equation below. Like most organic reactions, this can be described as an interaction between an electron rich species (nucleophile) and an electron deficient species (electrophile).

a) Examine the equation and clearly label each reactant as the nucleophile or electrophile as appropriate.

b) Write an equation to show how sodium phenoxide could be prepared from phenol (hydroxybenzene).

Answer 1

1:-

Hydrolysis reaction - it is the reaction in which bond in compound is broken ,the hydoxyl group and proton of water is added to each newly formed compounds.

Saponification reaction - it is the reaction in which oil or fat (triglycerides) are treated with alkaline water , the alkali reacts with triglyceride and result in the formation of corresponding alcohol and soap.

▪role of sodium hydroxide is shown in image.

2:-

Ibufroden s-form is non-selective inhibitor of cyclooxgenase enzyme

Whereas ibufrofen R-form does not binds effectively toh cyclooxygenase enzyme hence inactive ,

▪the structural difference is shown in image.

3:-

▪the steps of the reaction are shown in image.

▪the fish hook arrow represents the one electron transfer.

4:-

a- sodium phenoxide acts as nucleophile

Bromo ethyl acts as electrophile

b- reaction is shown in image