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We report herein the transfer of dual photoredox and nickel catalysis for C(sp2)C(sp3) cross coupling form batch to flow. This new procedure clearly improves the scalability of the previous batch reaction by the reactor's size and op

Under mild reaction conditions with inexpensive cerium and nickel catalysts, easily accessible free alcohols can now be utilized as operationally simple and robust carbon pronucleophiles in selective C(sp3)-C(sp2) cross-couplings. Facilitated by automated high-throughput experimentation, sterically encumbered benzoate ligands have been identified for robust cerium complexes, enabling the synergistic cooperation of cerium catalysis in the emerging metallaphotoredox catalysis. A broad range of free alcohols and aromatic halides can be facilely employed in this transformation, representing a new paradigm for the C(sp3)-C(sp2) bond construction between free alcohols and aryl halides with the extrusion of formaldehyde. Moreover, mechanistic investigations have been conducted, leading to the identification of a tribenzoate cerium(III) complex as a viable intermediate.

Metal-catalyzed intramolecular C?H amination of alkyl azides constitutes an appealing approach to alicyclic amines; challenges remain in broadening substrate scope, enhancing regioselectivity, and applying the method to natural product synthesis. Herein we report an iron(III) porphyrin bearing axial N-heterocyclic carbene ligands which catalyzes the intramolecular C(sp3)–H amination of a wide variety of alkyl azides under microwave-assisted and thermal conditions, resulting in selective amination of tertiary, benzylic, allylic, secondary, and primary C?H bonds with up to 95 % yield. 14 out of 17 substrates were cyclized selectively at C4 to give pyrrolidines. The regioselectivity at C4 or C5 could be tuned by modifying the reactivity of the C5–H bond. Mechanistic studies revealed a concerted or a fast re-bound mechanism for the amination reaction. The reaction has been applied to the syntheses of tropane, nicotine, cis-octahydroindole, and leelamine derivatives.