Synthesis of Rigid Macrocyclic Phenols and Their Catalytic Applications in Diels‐Alder Reactions

Abstract

Macrocyclic catalysts having a phenol‐acetylene‐phenol triad were developed as a hydrogen‐bond donor catalyst. The rigid macrocyclic framework suppressed intramolecular hydrogen bonds between neighboring phenolic hydroxy groups. The preorganized phenol‐acetylene‐phenol moiety formed efficient intermolecular hydrogen bonds with carbonyl groups of substrates. The hydrogen‐bond donor catalysts accelerated the Diels‐Alder reaction of methyl vinyl ketone with cyclopentadiene. The catalytic ability was higher than that of an acyclic counterpart.