14. Synthetic Techniques

Which of the following is the most appropriate first disconnection in the retrosynthetic analysis of ${\mathrm{Ph}}_2\mathrm{CO}$ (benzophenone)?

Which of the following statements best describes the purpose of retrosynthesis in organic chemistry?

Determine the structures of compounds A through G, including stereochemistry where appropriate.

Which of the following retrosynthetic disconnections is most appropriate for synthesizing $p_{-}\mathrm{nitroaniline}$ from readily available starting materials?

Given the target molecule ${\mathrm{Ph}}_2\mathrm{CO}$ (benzophenone), which of the following disconnections leads to the most reasonable retrosynthesis?

Supply the reagents necessary to accomplish the following transformation.

Propose a synthesis

Supply the reagents necessary to accomplish the following transformation.

Compound A (C₇H₁₁Br) is treated with magnesium in ether to give B (C₇H₁₁MgBr), which reacts violently with D₂O to give 1-methylcyclohexene with a deuterium atom on the methyl group (C). Reaction of B with acetone (CH₃COCH₃) followed by hydrolysis gives D (C₁₀H₁₈O). Heating D with concentrated H₂SO₄ gives E (C₁₀H₁₆), which decolorizes two equivalents of Br₂ to give F (C₁₀H₁₆Br₄). E undergoes hydrogenation with excess H₂ and a Pt catalyst to give isobutylcyclohexane. Determine the structures of compounds A through F, and show your reasoning throughout.

Show how you would convert the following starting materials into the target compound. You may use any additional reagents you need.

Using any necessary inorganic reagents, show how you would convert acetylene and isobutyl bromide to

(b) (±)-2,7-dimethyloctane-4,5-diol.

Beginning with the molecules on the left of each chemical equation, synthesize the molecules shown. While there can be multiple ways of doing each synthesis, the minimum number of steps necessary is indicated over each reaction arrow.

(a)

Synthesize the following molecules beginning with only organic molecules containing three carbons or fewer.

(g)

Beginning with the molecules on the left, provide a synthesis of the molecule on the right. The ideal number of steps is indicated over the reaction arrow, although there may be alternate routes worth considering.

(a)

Using the given starting material, any necessary inorganic reagents, and any carbon-containing compounds with no more than two carbons, indicate how the following syntheses could be carried out:

a.