The reactions of HCl, PCl5, and a crown ether (12-crown-4 or 18-crown-6) in CHCl3 under anaerobic conditions give complexes of the superacid HPCl6: [H(12-crown-4)][PCl6] and [H(18-crown-6)(2)][PCl6]. The crystal structures indicate that the proton lies roughly in the center of the 12-crown-4 molecule in [H(12-crown-4)][PCl6] whereas it lies between two oxygen atoms of two different 18-crown-6 molecules in [H(18-crown-6)(2)][PCl6].