A method of preparing dichloroformals of the formula by reaction of one mole of a thionocarbonate of the formula with two moles of benzenesulfenyl chloride, chlorobenzenesulfenyl chloride, r methanesulfenyl chloride wherein R is --C(NO.sub.2).sub.3, --CF(NO.sub.2).sub.2, --CF.sub.2 (NO.sub.2), --CCl(NO.sub.2).sub.2, --C(NO.sub.2).sub.2 CH.sub.3, --CCl.sub.3, --CF.sub.3, or --CF.sub.2 CF.sub.3. These energetic dichloroformals are useful as explosive and propellant ingredients and as intermediates in the synthesis of other energetic explosive and propellant ingredients.
