0. CHOOSE ONE OF THE FOLLOWING TWO PROBLEMS TO COMPLETE. Put an X through the problem you do not want graded. (10 points) (a) Propose a synthesis of the following molecule starting from two equivalents of 1,4-dibromobutane. Provide a retrosynthetic analysis or show all intermediate products in your synthesis. You must include all relevant reaction conditions (e.g. reagents, solvents, temperature, etc.) for the forward synthesis. 2 (b) Propose a reaction mechanism for the following transformation. Use curved arrow notation to show all electron movement and include stereochemistry where relevant. Include all lone pairs and formal charges