Covalent Folding of Fluorinated Polyphenylene by Sulfur Fluorine Annulative Substitution

Abstract We report that fluorinated polyphenylene P50 undergoes folding‐like sulfur fluorine annulative substitution (SFAS) to form a well‐defined tubular helix H50 . This is achieved with atomic precision in an exceptionally efficient manner, involving the simultaneous transformation of 98 C−F bonds with the yield per reaction site approaching 99.9 %. The desired product H50 features a fully fused dibenzothiophene skeleton of 5.8 helical turns in total. It is truly monodisperse ( Đ =1.0) in nature, allowing for thorough spectroscopic characterizations. Unambiguous single crystal X‐ray structure, distinct chiroptical properties, and intriguing through‐cavity threading complexation are described. These results, in addition to those of H50 ’s lower congeners, H34 and H18 , illustrate the great potential of folding‐like SFAS in shaping random‐coiled polymer chains into higher‐order functional structures.