Efficient post-macrocyclization functionalizations of oxacalix[2]arene[2]pyrimidines

Diversely functionalized oxacalix[2]arene[2]pyrimidines have been synthesized starting from a bis(methylsulfanyl)-substituted oxacalix[4]arene by two efficient post-macrocyclization pathways. Functionalized aryl groups were introduced on the pyrimidine building block via Liebeskind-Srogl cross-coupling reactions, while a variety of O-, S-, N-, and C-nucleophiles were inserted on the calixarene skeleton by nucleophilic aromatic substitution reactions on the bis(methylsulfonyl)oxacalix[4]arene analogue.