Question

Chemistry 326 Laboratory Manual 36 3a. Sketch the TLC that you observed after conversion of benzhydrol to benzophenone, but before recrystallization. Also list the Rf values for benzhydrol and benzophenone. Identify each spot. Note: if you did not perform TLC in lab, sketch your predicted results. (2 pts) Or1gin ecybydru Sovont tyont RF Benzhyarol RE:0.275 cm BenzoPhenone Rf: 0. Co5 cm .5 Fantomamm 3b. If you wanted the spots from 3a to travel farther on a silica gel TLC plate, what conditions would you change, without changing the plate? Be VERY specific. (1 pt) 3c. If we were to also analyze the starting reagent for the Grignard addition, bromobenzene, by TLC and compare it to benzophenone and benzhydrol, what order would it elute relative to the other two? Carefully consider the polarity differences and draw the expected TLC. (2 pts) Benzophenany Benzhydrol

Answer 1

201. EA Hexena — bnzephen 5cm 3cm benzhy dont Rt of benzophenone = 3 Rf of benz hydrol = 2 66 If you increase the from 20%. En in hexane polarity of satuent system to 40%. Ea in hexare. I - Bromo benzene (less polar) benzophenone no polar Benzhydral graugas medium polar more botar polar carbonyl more polar hydroxy group.