Selective synthesis of functionalized thia- and oxacalix[2]arene[2]pyrimidines

Functionalized oxacalixm]arenen]pyrimidines have been synthesized by S(N)Ar on 4,6-dihalopyrimidine building blocks. Depending on the S(N)Ar conditions, either a mixture of oxacalixn]arenes, ranging from oxacalix4]- up to oxacalix12]arene, could be prepared or the oxacalix4]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 oxacalix4]arenes. Moreover, the procedure also gives access to the analogous thiacalix4]arenes.