Green oxidations of furans—initiated by molecular oxygen—that give key natural product motifs

Abstract

In this article, we explore how changes in the positioning of pendant hydroxyl functionalities in the photooxygenation substrate dramatically alter the course of furan oxidations that are initiated by singlet oxygen; and, how these different reactivities can be harnessed through cascade reaction sequences to access, rapidly and effectively, a broad range of important natural product motifs.

One‐Pot Transformation of Simple Furans into 4‐Hydroxy‐2‐cyclopentenones in Water

“…Singlet oxygen is an ideal reagent for many reasons; one of the most important is because it fits very well into the modern paradigm which targets greater sustainability in chemistry 8a,c. Not only is this profile due to its intrinsic characteristics (atom economy, selectivity etc.…”

Singlet Oxygen and Dyes: Synthesis with Visible Light is Where the Future Lies

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A Divergent Synthesis of Spiropyrazole Derivatives Containing Iminolactone and/or Cyclic Imide Moiety

“…On the other hand, spirocompounds have also attracted the attention of organic and medicinal chemists because of their broad spectrum of biological activities . Hence, their synthesis continues to attract attention and provides an interesting challenge . In the literature, there is not much research related to the synthesis of spiropyrazole derivatives, even though they also have biological activities .…”