An aza-cyclophane stacked in racemic columnar assemblies: whole-molecule disorder in a twosdimensional solid solution

摘要

The oxime derivative of [1.1.1]cyclophane cyclotriveratrylene (CTé) was ring expanded utilizing a Beckmann rearrangement to provide a ten-membered N-acetyl macrocyclic amide that crystallizes as a chloroform monosolvate in columnar assembles manifesting an unusual disorder within the crystal.Columns made up of this structure consist of infinite columnar assemblies of alternating D and L enantiomers and therefore necessarily are made up of a racemate, yet the chiralities of individual molecules in adjacent columns are independent of one another, leading to the overall formation of a twodimensional solid solution. The random arrangement of the columns within the structure leads to the emergence of a crystallographic mirror plane not reflected by the molecular symmetry, to a change of symmetry from Рnа2_1 to Pama and to whole-molecule disorder of the bowl-shaped molecules within the columns.