Background: In recent years, photoredox catalysis using eosin Y has gained considerable
significance in organic chemistry. It is evolving as a powerful approach in modern organic synthesis
for the activation of small molecules.
Objective: The use of organic dyes to convert visible light into chemical energy by involving a
single-electron transfer with organic substrates has innumerable applications.
Method and Results: The present strategy is the first example of visible light promoted, aerobic,
oxidative cyclization of chromeno[4,3-b]chromenes and hexahydro-1H-xanthenes via the formation
of C–O and C–C bonds to afford excellent yield of the products in a simple one-pot operation under
mild reaction conditions.
Conclusion: The major advantages of the present methodology include short reaction time, cost effectiveness,
easy work-up, broad substrate scope and high atom economy.