Chloromethyl phenyl sulfides 3 underwent [4+ +2] type polar cyclo-additions with styrene, trans-stilbene, and phenylacetylene in the presence of stannicchloride to afford the thiochroman 4, 5 and thiochromen derivatives 6. Under the same reaction conditions, N-allyl-α-chloro-α-(phenylthio)acetamide (7) gave the intramolecular cycloaddition product 8.