Chlorine Monofluoride

image [7790‐89‐8] ClF (MW 54.45) InChI =  1S/ClF/c1‐2 InChIKey =  OMRRUNXAWXNVFW‐UHFFFAOYSA‐N (reagent used as a source of electrophilic chlorine and nucleophilic fluoride; formation of hypochlorites; synthesis of chloramines: dihalogenation of alkenes; oxidative fluorination of sulfur derivatives) Physical Data: Colorless gas at room temperature; colorless solid, mp −155.6 °C; pale yellow liquid, bp −100.1 °C; d 1.62 g cm −3 . Form Supplied in: pressurized container. Preparative Methods: gaseous chlorine monofluoride can be obtained by heating equimolar amounts of F 2 and Cl 2 at 230 °C in copper tubes, 1 or at 250 °C in nickel tubes using a 5% excess of Cl 2 . 2 Preparations involving silver salts or alkali metal fluorides upon heating have also been reported in addition with a method at low temperature using SbF 5 at 35 °C. 3 Other procedures have been described using ClF 3 with Cl 2 and CsF upon heating or with HgCl 2 at 25 °C. 4 ClF can also be prepared and used in situ by mixing N ‐chlorosuccinimide and HF. 5,6 Purification: depending on the preparative method, the major impurities are ClF 3 , HF, F 2 , and/or Cl 2 . Fractional condensation with a trap at –142 °C to retain impurities and a trap at –196 °C to condense pure ClF can be used. 4 Handling, Storage, and Precautions: chlorine fluorides are strong oxidizing agents and are toxic. Hydrolysis can produce shock‐sensitive chlorine oxides and toxic by‐products (ClO 2 F, Cl 2 , HF). ClF 3 is also a decomposition product and is highly pyrophoric. Protect from sunlight. Do not expose to temperatures above 50 °C. Keep the container closed when not in use. Reacts violently with metals and reducing agents. Appropriate shielding is required for high‐pressure work. Wear protective clothing and a face mask at all times.