Divergent 1,2-carboallylation of terminal alkynes enabled by metallaphotoredox catalysis with switchable triplet energy transfer

Abstract

We report a selective and stereodivergent three-component carboallylation of terminal alkynes with allylic carbonates and alkyl trifluoroborates via metallaphotoredox catalysis with pyrene as a triplet energy transfer (EnT) modulator.

Acetone Serving as a Solvent and Interaction Partner Promotes the Direct Olefination of N-Tosylhydrazones under Visible Light

“…Notably, when the benzene ring on both sides is replaced by halogen and methyl, the reaction showed good to excellent yields, indicating that hydrazones bearing both electron-withdrawing and electron-donating substituents were well tolerated in this reaction with high stereoselectivity. Surprisingly, the product 23b bearing two chlorine groups in the para position of the two phenyl rings, was isolated with 65% yield and mainly took ( Z )-olefins, which are hard to generate without photosensitizers, , as the main product. Moreover, N -tosylhydrazones derived from aryl ketones could still afford the desired products with excellent yields ( 24b ).…”

Tunable C–H functionalization and dearomatization enabled by an organic photocatalyst

“… 2 Both types of transformations have found broad applications in areas ranging from pharmaceuticals and agrochemicals to materials science. 3 Despite the great achievements made to date, the utilization of a single catalyst to promote tunable C–H functionalization and dearomatization processes from the same starting materials is underexplored. Elegant reports mainly involve the substrate control.…”