Facile Lewis Acid Catalyzed Synthesis of C₄ Symmetric Resorcinarenes

The Lewis acid catalyzed condensation of 3-methoxyphenol with octanal produced the C₄ symmetric calix[4]resorcinarene 2, in high yield. Of the numerous stereo- and regioisomers possible, the rccc isomer with C₄ symmetry was the only product isolated (as a racemate). The structure has been established by single-crystal X-ray structure analysis.