Science of Synthesis

Wang, M.; Li, P.; Wang, L., Science of Synthesis: Photocatalysis in Organic Synthesis, (2018) 1, 332.

Catalytic acceptorless dehydrogenation of saturated hydrocarbons and nitrogen heterocycles to produce aromatic compounds is a fundamentally important chemical process with numerous applications in organic synthesis.[‌77‌,‌78‌] Iridium–pincer complexes provide a privileged catalyst platform for such catalytic acceptorless dehydrogenation,[‌79‌–‌85‌] although rhodium,[‌86‌,‌87‌] nickel,[‌88‌] iron,[‌89‌] and cobalt complexes[‌90‌] also exhibit good reactivity. However, the dehydrogenation protocols require relatively harsh conditions, even in a homogeneous manner. Recently, the acceptorless dehydrogenation of tetrahydroquinolines, dihydroindoles, and tetrahydronaphthalenes at ambient temperature by merging visible-light photoredox catalysis and transition-metal catalysis has been developed, affording the corresponding dehydrogenated products in high yields.[‌91‌,‌92‌]

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References