A carefully curated review of the scientific literature, Volume 117 of Organic Reactions presents critical discussions of widely used organic reactions or particular steps of a reaction. The material is treated from a preparative viewpoint, with emphasis on limitations, interfering influences, effects of structure and the selection of experimental techniques. The work includes tables that list and compare relevant examples of the reaction under consideration. Detailed procedures illustrate the significant modifications of each method. Launched in 1942, the Organic Reactions series today is a leading secondary- and tertiary-level source for organic chemists across the world.