Induced-fit conformational changes in the cation–π complexes of pyxophane: a DFT study†
Abstract
In contrast to the proposed structures of 1 ∶ 1 complexes of the chair-form pyxophane1 with Na+ and `external' 2 ∶ 1 complexes with K+, DFT calculations suggest that 1 prefers the saddle-form in the complexes due to the induced-fit conformational change and that 1 forms an `internal' 2 ∶ 1 complex with K+.