ABSTRACT
A protocol for trans-hydroboration of indole derivatives using heterogeneous photocatalysis with NHC-borane has been developed, addressing a persistent challenge in organic synthesis. The protocol, leveraging high crystalline vacancy-engineered polymeric carbon nitride as a catalyst, enables diastereoselective synthesis, expanding substrate scope and complementing existing methods. The approach emphasizes eco-friendliness, cost-effectiveness, and scalability, making it suitable for industrial applications, particularly in renewable energy contexts. The catalyst's superior performance, attributed to its rich carbon-vacancies and well-ordered structure, surpasses more expensive homogeneous alternatives, enhancing viability for large-scale use. This innovation holds promise for synthesizing bioactive compounds and materials relevant to medicinal chemistry and beyond.
ABSTRACT
A feasible and effective method to synthesize α-fluoroalkenyl alcohols was reported. With the cooperation of photoredox and hydrogen atom transfer (HAT) processes, defluoroalkylations of gem-difluoroalkenes occurred smoothly with alcohols under visible-light irradiation. Notably, the protocols feature broad scopes, mild conditions, and validity for the late-stage functionalization of bioactive molecule derivatives. Mechanistic studies suggested that the reaction occurred through the radical coupling of the alkyl radical and the fluoroalkenyl radical.
ABSTRACT
Direct and selective fluoroarylations of nucleophilic secondary alkylanilines with polyfluoroarenes were first realized through visible-light-induced C-H/C-F couplings with the assistance of bases. Varieties of α-polyfluoroarylanilines were selectively produced with this protocol from polyfluoroarenes and N-alkylanilines, including natural products and pharmaceutical molecule derivatives. Mechanistic studies illustrated base-promoted photochemical C-H cleavage of the α-C-H bonds of alkylanilines to produce the N-α-carbon radical and then radical addition to polyfluoroarenes.
Subject(s)
Aniline Compounds , Light , Aniline Compounds/chemistry , Catalysis , Molecular Structure , Carbon/chemistryABSTRACT
To provide α-polyfluoroarylalcohols, a novel protocol for the selective defluoroalkylation of polyfluoroarenes with easily accessible alcohols was reported via the cooperation of photoredox and hydrogen atom transfer (HAT) strategies with the assistance of Lewis acids under visible light irradiation. The protocol featured broad scope, excellent regioselectivity for both C-H and C-F bond cleavages, and mild conditions. Mechanistic studies suggested that the reaction occurred through Lewis acid-promoted HAT to provide an alkyl radical and sequential addition to polyfluoroarenes. Impressively, the regioselectivity for C-F cleavage was verified with the Fukui function. The feasibility and application of this protocol on fluoroarene synthesis were well illustrated by gram-scale synthesis under both batch and flow conditions, late-stage decoration of bioactive compounds, and further transformations of the fluoroarylalcohols.
