The yield of phenylalanine from the reaction between benzyl chloride and ammonia depends on the specific reaction conditions, such as temperature, pressure, concentration, and catalysts used. Without knowing the exact conditions, it is difficult to provide an exact yield percentage.However, to optimize the yield of phenylalanine from this reaction, you can consider the following factors:1. Temperature: Ensure that the reaction is carried out at an optimal temperature, which can vary depending on the catalyst used. Generally, increasing the temperature can increase the reaction rate, but be cautious not to exceed the temperature limit of the reactants or catalysts.2. Pressure: Adjust the pressure to favor the formation of phenylalanine. Higher pressure can increase the reaction rate, but it may also cause side reactions or degradation of the reactants.3. Concentration: Use an appropriate concentration of benzyl chloride and ammonia to maximize the yield of phenylalanine. Too high or too low concentrations can lead to side reactions or incomplete reactions, respectively.4. Catalysts: Employ a suitable catalyst to increase the reaction rate and selectivity towards phenylalanine formation. Transition metal catalysts, such as palladium or nickel complexes, can be used to facilitate the reaction.5. Reaction time: Allow the reaction to proceed for an optimal duration to maximize the yield of phenylalanine. Too short reaction times may result in incomplete reactions, while too long reaction times can lead to side reactions or degradation of the product.6. Purification: Optimize the purification process to separate phenylalanine from the reaction mixture efficiently. Techniques such as crystallization, chromatography, or extraction can be used to isolate the product.By carefully controlling these factors, you can optimize the yield of phenylalanine from the reaction between benzyl chloride and ammonia. However, it is essential to note that this reaction may not be the most efficient or practical method for synthesizing phenylalanine, as there are alternative routes with higher yields and fewer side reactions.