The possibility of synthesis of 1,4-thioxanes of allyl series by interaction of corresponding thiiranes with ethylenechlorhydrin in the presence of etherate of trifluoride boron and further dehydrochlorination of the prepared chlorohydrins in the presence of metallic sodium in medium of absolute diethyl ether has been shown. The synthesized 1,4-thioxanes undergo the reactions of epoxidation and dehydrohalogenation on double bond with formation of new derivatives of 1,4-thioxane