OAT Organic Chemistry 2

Question 1

Which reagent converts a primary alcohol to an aldehyde without over-oxidizing to a carboxylic acid?

Accepted Answer

PCC (pyridinium chlorochromate)

Answer

PCC oxidizes primary alcohols to aldehydes and stops there because it is used in anhydrous conditions.

Question 2

In an E2 elimination reaction, the leaving group and the β-hydrogen must be in what geometric relationship?

Accepted Answer

Anti-periplanar (180°)

Answer

E2 requires a concerted anti-periplanar arrangement so the base, β-H, Cα, and leaving group are all coplanar.

Question 3

What is the product when benzene reacts with Cl2 in the presence of FeCl3?

Accepted Answer

Chlorobenzene

Answer

FeCl3 activates Cl2 as an electrophile, enabling electrophilic aromatic substitution to give chlorobenzene.

Question 4

Which of the following molecules exhibits optical activity?

Accepted Answer

2-butanol

Answer

2-Butanol has a chiral center (C2 bonded to OH, H, CH3, and C2H5), making it optically active.

Question 5

Which functional group is introduced when a terminal alkyne reacts with water in the presence of H2SO4 and HgSO4?

Accepted Answer

Ketone

Answer

Markovnikov addition of water to an internal position of a terminal alkyne forms a methyl ketone via an enol intermediate.

OAT - Optometry Admission Test Practice Test