A series of new tolane liquid crystals with piperidine and 3,3,4,4,5,5-hexafluoropiperidine as their terminal groups were synthesized via Sonagashira reaction by using Pd(PPh 3 ) 2 Cl 2 /CuI as the catalyst. Their structures were modified by varying the terminal N-heterocycles and/or the length of the alkyl/alkoxy chains on the benzene ring. Most of these new compounds exhibit Smectic B or G mesophases, good thermal stabilities and high clearing points. The molecule C 2 H 5 O6F with 3,3,4,4,5,5-hexafluoropiperidine as the end group has a broader HOMO–LUMO energy gap and higher oxidation potential than piperidine derivative C 2 H 5 O6H. The result indicates that the oxidation resistance of the tolane liquid crystals was improved by introducing the terminal fluorinated piperidine.