Steroids are an extremely important class of natural and pharmaceutical compounds. Synthetic efforts directed toward steroids have been underway for many years and continue to be an area of important research. The synthesis of cholesterol by R. B. Woodward (Harvard University, recipient of the Nobel Prize in Chemistry for 1965) and co-workers represents a paramount accomplishment in steroid synthesis, and it is rich with examples of carbonyl chemistry and other reactions we have studied. Selected reactions from Woodward’s cholesterol synthesis and the questions for this Learning Group Problem are shown in the WileyPlus materials for this chapter. Access those materials online to complete this problem.