A Facile and Efficient Preparation of Pillararenes and a Pillarquinone

Ring around the roses: The ipso substitution of benzene rings makes a simple and efficient synthesis of pillar[n]arenes (n=5, 6) possible. Pillar[6]arenes (see picture) and pillar[5]quinone, an oxidation product of pillar[5]arene, are novel, highly promising host systems for host–guest chemistry.