Discover CoolMate microwave synthesis system performs sub-ambient temperature chemistries for temperature-sensitive reactions including carbohydrate chemistry and the formation of carbanions and other highly reactive intermediates. The system also allows the safe use of highly reactive species. A proprietary, jacketed, low-temperature vessel and cooling technology keep the bulk temperature of the reactants low, preventing thermal degradation of the product while microwave energy drives the reaction kinetically. Temperature measurement is accomplished with an in situ fiber-optic probe to insure fast, accurate, and convenient reaction feedback control.