Insight into 6π Electrocyclic Reactions of 1,8‐Dioxatetraene

Upon exposure to light, benzofuranone‐based spiroisochromenes undergo isomerization to give 1,8‐dioxatetraene intermediates. The stability of the intermediate is governed by its steric congestion and can be fine‐tuned through modification of the backbone structure, leading to the emergence of photochromic properties.

Abstract

A variety of benzofuranone‐based spiroisochromenes were originally designed and synthesized to gain insight into the oxa‐6π electrocyclic reaction of cis,cis‐1,8‐dioxatetraene for the first time. The stability of the 1,8‐dioxatetraene intermediate is governed by its steric congestion and can be fine‐tuned through modification of the backbone structure, leading to the reactivity differences in the 6π electrocyclic reaction and the emergence of photochromic properties.

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