Abstract
<jats:p>Photocatalysis is a transformative tool in synthetic chemistry. However, its sustainability is limited due to the reliance on non-abundant and expensive transition metal-based and waste-generating organic dyes as photocatalysts. Efficient approaches eliminating the need for a photocatalyst, by relying only on the photoactive nature of the substrate, are highly attractive, yet remain rare. We report the first self-catalyzed, visible-light induced electrocyclization reaction that enables direct access to new chromenopyrazolines from readily available acyl hydrazones, without the need for external photocatalysts or additives. This photo-autocatalytic strategy exploits the substrates’ intrinsic photoactivity, i.e. light initiated E/Z-isomerization and change in NH acidity, to drive electrocyclization, obviating external photocatalysts and minimizing waste. The reaction proceeds under very mild conditions to deliver chromenopyrazolines in up to 96% yield. By uniting operational simplicity, atom economy, and environmental compatibility, this work establishes a green and broadly applicable platform for constructing chromenopyrazoline frameworks of relevance to life science.</jats:p>