Heterocyclic compounds have played a significant role in the field of photochromism with applications ranging from energy production, chemical sensing, and molecular actuators to biological systems. While heterocyclic photochromic materials can be of both P-type and T-type, herein we focus on the background, synthesis, properties, and applications of specifically T-type photochromic compounds derived from heterocycles. It is the goal of this chapter to bring greater attention to these emergent architectures in the hopes of further advancing their role in the field.

A one-pot synthesis of anilines and nitrosobenzenes from phenols has been developed using an ipso-oxidative aromatic substitution ((i)SOAr) process. The products are obtained in good yields under mild and metal-free conditions. The leaving group effect on reactions that proceed through mixed quionone monoketals has also been investigated and a predictive model has been established.