DeanStarktyyppiset

DeanStarktyyppiset, often referred to as Dean-Stark apparatuses, are specialized laboratory glassware used in organic chemistry to remove water or other liquids from a reaction mixture through azeotropic distillation. The apparatus consists of a distillation flask, a condenser, and a graduated side arm designed to collect the distillate. As the reaction mixture is heated, vapors rise and are condensed. The condensed liquid then collects in the side arm. If the condensed liquid is immiscible with the reaction solvent, such as water and an organic solvent, the denser liquid will settle at the bottom of the side arm, while the less dense liquid will overflow and return to the distillation flask. This continuous removal of water drives equilibrium reactions to completion, particularly esterifications, acetal formations, and dehydrations. The design allows for monitoring the amount of water removed, providing insight into the progress of the reaction. Invented by Ernest W. Dean in 1920, the Dean-Stark apparatus is a common sight in organic synthesis laboratories and is a crucial tool for achieving high yields in water-sensitive reactions.