Chloral Hydrate CasNo.: 302-17-0 is a geminal diol with the formula C2H3Cl3O2. It is a colorless solid. It has limited use as a sedative and hypnotic pharmaceutical drug. It is also a useful laboratory chemical reagent and precursor. It is derived from chloral (trichloroacetaldehyde) by the addition of one equivalent of water.Moreover, chloral hydrate is used as a reagent for the deprotection of acetals, dithioacetals and tetrahydropyranyl ethers in organic solvents.