Organic Chemistry Laboratory I - Chem 341

Quiz 10d

1. Why does excess of base used in the elimination reactions favor the E2 over the E1 mechanism? (1 pt)

The E2 elimination is kinetically second-order and is affected by the base and alkyl halide concentration; thus, it is accelerated by an increase in base concentration. However, the E1 reaction, is first-order and the rate only depends on the concentration of alkyl halide; thus, increasing the base concentration has little effect on the rate for the E1 mechanism.

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-1-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. Teflon is produced from the polymerization of tetrafluoroethene. Write the structure of Teflon showing the monomeric unit in parenthesis. (2 pts)

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