To an ice-cooled dry flask containing 25.0 gm (0.18 mole) of s-trithiane is slowly added dry chlorine gas. As soon as the solid liquefies, the temperature is raised to 10-20°C, and approximately a total of 57.0 gm (0.80 mole) of chlorine gas is absorbed. The product is distilled under reduced pressure to afford 9.9-12.9 gm (46-60%), b.p. 30°C (10 mm Hg).
