4. The Wittig reaction of 4-bromobenzaldyde with benzyltriphenylphosphonium chloride (below) requires a base. Why is a base not required for the Wittig reagent (ethoxycarbonylmethylene) triphenylphosphorane used in this experiment to synthesize ethyl cinnamate? ( 1 point) 5. Draw the curved-arrow mechanism of the reaction. Clearly show how both E and Z isomers may be formed and explain why the E isomer is favored. Do not copy and paste from someone else's work; must be original. (3 points)