A novel host framework of cholic acid inclusion crystals by slide and flip of the layers

Abstract

A novel host framework of cholic acid (CA) has been observed in the crystal structure of m-chloroaniline clathrate. Crystallographic study reveals that CA forms a bilayer-type structure; however, slide and flip of the lipophilic layers give a different host framework to those of over 100 inclusion crystals previously reported. Structural comparison between the clathrates of aniline and m-chloroaniline indicates that the addition of a chlorine atom leads to isomerization of the open host framework due to a steric effect between adjacent guests within the host cavities.