posted on 2024-01-04, 17:04authored byPartha
Pratim Sen, Nayan Saha, Sudipta Raha Roy
Implementation of an organic molecular photocatalyst
for photoelectrochemical
(PEC) transformations has been a highly demanding aspect that has
not yet been mapped out extensively. Herein, we have unveiled the
efficacy of a phenalenyl-based organic photocatalyst toward photoelectrochemical
intramolecular C–S bond construction reactions under mild conditions.
This phenalenyl core, which contains a vacant NBMO, acts as an electron
reservoir, thereby facilitating the formation of a contact ion pair
with electron-rich organic systems through intramolecular electron
transfer under photoexcitation and aiding in catalytic regeneration
by anodic oxidation in a single pot. Detailed mechanistic investigation
by using UV–visible spectral analysis, cyclic voltammetry experiments,
and computational calculations revealed that the prior formation of
an EDA complex between the phenalenyl-based photocatalyst and substrate
triggers this PEC process. This unified strategy was successfully
implemented in six different intramolecular C–S bond formation
reactions to synthesize different heterocycles and make this protocol
appealing for the synthesis of C–S bonds.