X-ray crystal structure and1H-NMR chiral shift reagent study of a crown trimer

3,4,5-Trimethoxybenzyl alcohol was cyclooligomerized with a bentonite clay used as a catalyst. Results of the crystal structure analysis of the racemic (±) nonamethoxy1,1,1]orthocyclophane trimer, C₃₀H₃₆O₉, are described. The structure was determined by X-ray diffraction at 293 K and shown to belong to the triclinic space group P . The compound possesses a distorted crown conformation with unusual C–H...O intermolecular interactions, and with a crystal packing not observed before in other related derivatives. The racemic mixture was also discriminated in its two enantiomeric isomers, using proton NMR and Eu(III) as a chiral shift reagent.