Unlocking the Photocatalytic Oxidative Dehydrogenative Performance of a Polyoxomolybdate: The Cross-Coupling of P(O)H Compounds and Thiols

We disclose herein the oxidative dehydrogenation performance
of
a Lindquist-type polyoxomolybdate, [N(C4H9)4]2[Mo6O19], with irradiation
with visible light. The formulated inorganic molecular Mo6 photocatalyst can facilitate, with high efficiency, the cross-dehydrogenative
coupling of P(O)H compounds and thiols in water with ambient oxygen
as the oxidant. Moreover, a gram-scale reaction can smoothly proceed
under a simple, low catalyst loading system with high turnover numbers.
This catalyst exhibited good stability and reusability after at least
six turns of the reaction and even showed satisfactory photocatalytic
activity under sunlight irradiation. Bypassing using complicated organic
ligands and noble metal-based photosensitizers, this easily available,
cheap, and recyclable hexamolybdate represents an alternative photocatalyst
to realize oxidative dehydrogenative processes under metal-, base-,
and external-oxidant-free conditions.