Catalysis enabled synthesis, structures, and reactivities of fluorinated S8-corona[n]arenes (n = 8–12)

Abstract

Previously inaccessible large S₈-corona[n]arene macrocycles (n = 8–12) with alternating aryl and 1,4-C₆F₄ subunits are easily prepared on up to gram scales, without the need for chromatography (up to 45% yield, 10 different examples) through new high acceleration S_NAr substitution protocols (catalytic NR₄F in pyridine, R = H, Me, Bu). Macrocycle size and functionality are tunable by precursor and catalyst selection. Equivalent simple NR₄F catalysis allows facile late-stage S_NAr difunctionalisation of the ring C₆F₄ units with thiols (8 derivatives, typically 95+% yields) providing two-step access to highly functionalised fluoromacrocycle libraries. Macrocycle host binding supports fluoroaryl catalytic activation through contact ion pair binding of NR₄F and solvent inclusion. In the solid-state, solvent inclusion also intimately controls macrocycle conformation and fluorine–fluorine interactions leading to spontaneous self-assembly into infinite columns with honeycomb-like lattices.