PhI(OAc)₂‑Mediated Synthesis of 6‑(Trifluoromethyl)phenanthridines by Oxidative Cyclization of 2‑Isocyanobiphenyls with CF₃SiMe₃ under Metal-Free Conditions

A mild and efficient method for the synthesis of 6-(trifluoromethyl)phenanthridines through oxidative cyclization of 2-isocyanobiphenyls with CF₃SiMe₃ under metal-free conditions was developed. The reaction allows the direct formation of C–CF₃ bonds and rapid access to phenanthridine ring systems in one catalytic cycle

Synthesis of 3‑Acylindoles by Visible-Light Induced Intramolecular Oxidative Cyclization of <i>o</i>‑Alkynylated <i><i>N,N</i></i>-Dialkylamines

A visible-light photoredox synthesis of 3-acylindoles through intramolecular oxidative cyclization of <i>o</i>-alkynylated <i><i>N,N</i></i>-dialkylamines is developed. The reaction proceeds effectively under mild reaction conditions using air as the oxidant, and only water is generated as a side product. A plausible mechanism involving the addition of α-amino alkyl radicals to alkynes, followed by C–O bond formation, is proposed

Nickel-Catalyzed Enantioselective Hydrothiocarbonylation of Cyclopropenes

Hydrothiocarbonylation of olefins using carbon monoxide and thiols is a powerful method to synthesize thioesters from simple building blocks. Owing to the intrinsic challenges of catalyst poisoning, transition-metal-catalyzed asymmetric thiocarbonylation, particularly when utilizing earth abundant metals, remains rare in the literature. Herein, we report a nickel-catalyzed enantioselective hydrothiocarbonylation of cyclopropenes for the synthesis of a diverse collection of functionalized thioesters in good to excellent yields with high stereoselectivity. This new method employs an inexpensive, air-stable nickel(II) precursor, which provides enhanced catalyst fidelity against CO poisoning compared to nickel(0) catalysts