First Synthesis of Lower-Rim-Substituted Aryl Ethers of p-tert-Butylcalix[4]arene

Abstract
With the use of SNAr or Ullmann reactions, the synthesis of the first lower-rim aryl ether derivatives of tert-butylcalix[4]arene is reported, as are some of their conformational properties, 1H NMR spectra, and X-ray crystal structures. The lower-rim aryl pendants reported herein provide for new scaffolds upon which a host of other new molecular architectures can be constructed, thus extending the capability of the versatile calix[4]arenes even further.