Organic Synthesis by Relay Towards the end of the first-quarter organic chemistry wurse, I have found that students benefit from and enjoy a competitive round of synthetic relays. Our small dass size is ideally suited for dividing the class into two teams of &8 students each. Larger classes may divide into more or larger teams or may do this in lab sections where the class size is smaller. The teams race each other at the chalkboard to devise plausible syntheses. The teams are given a target wmpound and either a starting structure or set of limitations for designing a synthesis. The rules are simple: the team members may talk among themselves ta farm a synthetic plan, and take turns writing the synthesis on the board. Each person, in relay form, may do one of the following: write the conditions for the next reaction, draw the product of the reaction from the conditions the previous person wrote, or erase errors. I a m very strict about each person contributing although this is not usually a problem. The syntheses are designed ta be accomplished ideally in four or five steps but they can usually be solved in several ways. I have found that nearly all the students in the class can benefit from this. The teams generally try one or more poor approaches before arriving at a successful synthesis. The weakest students who are often reluctant to ask questions in class have a chance to clarify any misconceptions about individual reactions that are used. The stronger students hone their analytical thinking skills and hear how others might approach the same problem. After one team completes the problem, we spend a few minutes discussing possible approaches and why some strategies didn't work. Four or five prohlems during a class period can reinforca many of the reactions from the term without the novelty wearing out. This sort of exercise is best done at the end of the term when students have a respectable arsenal of reactions. It also makes a great review for the final exam, but the emphasis is on allowing students to learn from their mistakes. In general, with the head-to-head competition, students are having far tca much fun to realize how much they are learning.
Thomas D. Crute Augusta College Augusta, GA 30910
Volume 69 Number6 July 1992
559
