Chemoselective ring closure of thiacalix[4]arene-1,3-bis(N-ω-hydroxyalkylamides) via the Mitsunobu reaction

Thiacalixarene 1,3-bis(hydroxyalkyl)amides selectively cyclize to inherently chiral, doubly capped molecules under the Mitsunobu protocol. Self-condensation on the carboxamide groups to afford O,N-heterocycles was not observed.