Spirodienone and Bis(spirodienone) Derivatives of Calix[4]naphthalenes

Abstract

Calix[4]naphthalenes 11 and 12 in which hydroxyl groups are situated intraannularly can be oxidized with PTMATB and base to form the bis(spirodienone) 13, from 11, and bis(spirodienone) 20−21 and spirodienone 22, from 12. The prototype calix[4]naphthalenes 9 and 10 previously reported by us and which contain similar 1,5 dihydroxy functionalities extrannularly failed to afford the analogous spironaphthalenones. Model studies with the bis(1-hydroxy-2-naphthyl)methanes 8−8f provided support for the putative mechanism proposed for the formation of spirodienone calix[4]arenes and spironaphthalenones. The synthesis of the novel tert-butylcalix[4]naphthalenes 12 is described.