The separation of benzene and cyclohexane
is one of the most challenging
tasks in the petrochemical field. However, conventional separation
methods suffer from cumbersome operation, huge energy expenditure,
or use of entrainers. Herein, we develop an environmentally friendly
and energy saving adsorptive separation strategy using nonporous adaptive
crystals of a hybrid[3]arene (1). Adaptive 1 crystals separate benzene from an equimolar benzene/cyclohexane
mixture with a purity of 97.5%. The selectivity comes from the stability
and variability of the new crystal structure upon capture of the preferred
guest, benzene. Moreover, reversible transformations between the nonporous
guest-free structure and the guest-containing structure make 1 highly recyclable.