Selective Synthesis of Functionalized Thia- and Oxacalix[2]arene[2]pyrimidines

Functionalized oxacalix[m]arene[n]pyrimidines have been synthesized by SNAr on 4,6-dihalopyrimidine building blocks. Depending on the
SNAr conditions, either a mixture of oxacalix[n]arenes, ranging from oxacalix[4]- up to oxacalix[12]arene, could be prepared or the oxacalix[4]arene could be synthesized selectively in a high yield. The electrophilic (pyrimidine) and the nucleophilic components could both be varied,
allowing the preparation of functionalized oxacalix[4]arenes. Moreover, the procedure also gives access to the analogous thiacalix[4]arenes.