Visible Light-Induced Oxy-perfluoroalkylation of Olefins via Ternary Electron Donor-Acceptor Complexes.

Perfluoroalkyl iodides generally formed electron donor-acceptor (EDA) complexes by halogen bonding with a nitrogen atom containing Lewis bases. Since the electronegativity of the oxygen atom is stronger than that of the nitrogen atom, the resulting Rf-I···O-type halogen bonding EDA complex is less inclined to undergo electron transfer. Here, we reported rare ternary EDA complexes among perfluoroalkyl iodide, oxygen atom, and base. Mechanism experiments and density functional theory theoretical (DFT) calculations indicated that a base-promoted proton-coupled electron transfer (PCET) process was involved in this photochemical reaction. The intracomplex electron transfer event generated two radical species, perfluoroalkyl radical and TEMPO radical, enabling the subsequent oxy-perfluoroalkylation of olefins.

Direct synthesis of C3-alkynyl pyrroloindolines from tryptamines via a visible-light-induced radical cascade reaction.

A visible-light-induced radical cascade reaction for the direct alkynylation of tryptamines with alkynyl sulfones was developed, affording a series of C3-alkynyl pyrroloindolines in excellent yields. This method features readily available substrates, good functional group tolerability, and scalability. C3-alkynyl pyrroloindolines show great potential as useful building blocks in the preparation of complex and valuable pyrroloindoline alkaloids.

Retro-biosynthetic construction of corynanthe alkaloid skeletons from rhynchophylline alkaloids.

Rhynchophylline alkaloids are bio-synthesized from corynanthe alkaloids via an oxidative rearrangement. We demonstrate here that corynanthe alkaloids could be generated from rhynchophylline alkaloids in a retro-biosynthetic manner via a Wagner-Meerwein rearrangement. A series of corynanthe analogues were afforded with good functional group tolerance and satisfactory yields.