Previous papers2v3 described the photochemical monochlorination of some fluorinated aliphatic ethers. The present paper reports (with some correction of previous data) a complete study of the products isolated in the stepwise photochemical chlorination of CH3-O- CF2CFClH and CH3CH2-0-CFzCFCIH in the liquid phase. The chlorination of CH3-O- CFZCFClH went easily and stepwise to CCI3-O-CF2CFCIH then, after some lag, to CCl3- ...