Path to Industrial Production of Calix[8 and 4]arenes.

A highly selective and high yield synthesis for the production of calix[8]arenes in concentrated reaction masses is described. Obtained purities are >98% and yields of >80%, with isolation by simple filtration. The developed approach allows for subsequent "in situ" formation of calix[4]arenes. The syntheses are amenable to large scale manufacturing. Kinetic observations during the formation of calix[4]arenes from calix[8]arenes are included. Furthermore, details related to "soluble" calix[4]arene are described.