Crystal structure and conformational diversity of fluorinated alkyl tosylates

Crystal structures of fluorinated alkyl tosylates TsOCH2CF2CHFCF3 and TsOCH2(CF2)3CHF2 have been characterized by X-ray diffraction and quantum chemical calculations. The calculations have revealed the stabilization of head-to-tail conformation for TsOCH2CHFCF2CF3 due to intramolecular F・・・p and C–H・・・π interactions. Alternatively, for TsOCH2(CF2)3CHF2 these interactions cannot be responsible for the stabilization of head-to-tail conformation, thus the linear conformation is proved to be more stable.