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Herein, an I2‐catalyzed unprecedented cycloisomerization of ynamides is developed, furnishing various functionalized bis(indole) derivatives in generally good to excellent yields with wide substrate scope and excellent atom‐economy. This protocol not only represents the first molecular‐iodine‐catalyzed tandem complex alkyne cycloisomerizations, but also constitutes the first chemoselective cycloisomerization of tryptamine‐ynamides involving distinctively different C(sp3)−C(sp3) bond cleavage and rearrangement. Moreover, chiral tetrahydropyridine frameworks containing two stereocenters are obtained with moderate to excellent diastereoselectivities and excellent enantioselectivities. Meanwhile, cycloisomerization and aromatization of ynamides produce pyrrolyl indoles with high efficiency enabled by I2. Additionally, control experiments and theoretical calculations reveal that this reaction probably undergoes a tandem 5‐exo‐dig cyclization/rearrangement process. [ABSTRACT FROM AUTHOR]

An Ir‐catalyzed remote dearomatizative amidation for the enantioselective construction of chiral spirolactams in 70–93% yield with 81–96% ee was developed. This protocol represented a more atom‐economical approach to chiral spirolactams via Ir‐catalyzed nitrenoid transfer without the introduction of a traceless O‐silyl achiral auxiliary. [ABSTRACT FROM AUTHOR]

Summary of main observation and conclusion: An efficient NaBArF4‐catalyzed oxidative cyclization of readily available 1,5‐ and 1,6‐diynes has been developed. Importantly, this transition metal‐free oxidative catalysis proceeds via a presumable Lewis acid‐catalyzed SN2' pathway, which is distinct from the relevant oxidative rhodium and gold catalysis. This method leads to the facile and practical construction of a diverse range of synthetically useful γ‐ and δ‐lactams in mostly good to excellent yields with broad substrate scope. We report a NaBArF4‐catalyzed oxidative cyclization of 1,5‐ and 1,6‐diynes via a presumable Lewis acid‐catalyzed SN2' pathway. This method leads to the efficient and practical construction of a diverse range of synthetically useful γ‐ and δ‐lactams in mostly good to excellent yields with broad substrate scope. [ABSTRACT FROM AUTHOR]

A novel copper-catalyzed tandem cyclization/direct C(sp 2 )-H annulation of phenyl azide-ynamides via α-imino copper carbenes has been developed, which provides a concise and flexible approach for the construction of a range of valuable azepino[2,3- b :4,5- b ']diindoles in mostly good to excellent yields with high chemoselectivities. This tandem reaction also exhibits a broad substrate scope, excellent functional group tolerance, simple operation, and mild reaction conditions.

Herein, an I 2 -catalyzed unprecedented cycloisomerization of ynamides is developed, furnishing various functionalized bis(indole) derivatives in generally good to excellent yields with wide substrate scope and excellent atom-economy. This protocol not only represents the first molecular-iodine-catalyzed tandem complex alkyne cycloisomerizations, but also constitutes the first chemoselective cycloisomerization of tryptamine-ynamides involving distinctively different C(sp 3 )-C(sp 3 ) bond cleavage and rearrangement. Moreover, chiral tetrahydropyridine frameworks containing two stereocenters are obtained with moderate to excellent diastereoselectivities and excellent enantioselectivities. Meanwhile, cycloisomerization and aromatization of ynamides produce pyrrolyl indoles with high efficiency enabled by I 2 . Additionally, control experiments and theoretical calculations reveal that this reaction probably undergoes a tandem 5-exo-dig cyclization/rearrangement process., (© 2022 Wiley-VCH GmbH.)

In the title salt, (C(8)H(15)N(3))[CoCl(4)], the four chloride anions coordinate the Co(II) ion in a distorted tetra-hedral geometry. In the crystal, N-H⋯Cl hydrogen bonds link cations and anions into chains running along the c axis. The crystal packing is further stabilized by weak C-H⋯Cl and C-H⋯N inter-actions.

In the title compound, [CoCl(3)(C(6)H(13)N(2))], the tetra-hedrally coordinated Co(II) ion has Co-Cl distances ranging from 2.2220 (11) to 2.2449 (9) Å and a Co-N distance of 2.056 (2) Å. In the crystal, N-H⋯Cl hydrogen bonds link mol-ecules into chains in [010]. Weak C-H⋯Cl inter-actions stabilize further the crystal packing.