Organic Chemistry Laboratory I - Chem 341

Quiz 10a

1. What is the solid material that precipitates out of solution as the elimination reaction proceeds? (1 pt)

This is potassium bromide (KBr).

2. Circle the major organic product from the following reaction. (1 pt)

3. Circle the monomer in the polymer below. (1 pt)

4. Circle the confirmation that best represents the transition state for an E2 elimination that would result in the formation of 2-methyl-2-butene (2 pts)

The leaving group (Br) and the hydrogen atom must be antiperiplaner to each other.

5. Is Nylon synthesized by a step-growth or chain-growth mechanism? (1 pt)

Nylon is synthesized by a step-growth mechanism. In the step-growth process the monomers have reactive functional groups at both ends of the monomer. These combine to form small chains, which then combine to form medium chains, etc.

6. Explain why the preparation of Nylon-6,10 occurs under milder conditions when decanedioyl dichloride is used instead of decanedioic acid. (2 pts)

Decanedioyl dichloride possesses two acid chloride groups, which react much more rapidly with the primary amine groups of 1,6-hexanediamine than with a carboxylic acid group. This is because Cl^- is a better leaving group than ^–OH.

7. Propose an arrow pushing mechanism for the bromine test. (2 pts)