Bis(chloroethyl) ether is an organic compound with the formula O(CH<sub>2</sub>CH<sub>2</sub>Cl)<sub>2</sub>. It is an ether with two 2-chloroethyl substituents. It is a colorless liquid with the odor of a chlorinated solvent.
Bis(chloroethyl) ether is less reactive than the corresponding sulfur mustard S(CH<sub>2</sub>CH<sub>2</sub>Cl)<sub>2</sub>. In the presence of base, it reacts with catechol to form dibenzo-18-crown-6:
Bis(chloroethyl) ether can be used in the synthesis of the cough suppressant fedrilate. It is combined with benzyl cyanide and two molar equivalents of sodamide in a ring-forming reaction. When treated with strong base, it gives divinyl ether, an anesthetic:
The is 74 mg/kg (oral, rat). Bis(chloroethyl) ether is considered as a potential carcinogen.