A mild catalytic system for radical conjugate addition of nitrogen heterocycles

Abstract

A catalytic redox system for the direct conjugate addition of pyridines and diazines to Michael acceptors has been developed.

Experimental and Computational Studies Unraveling the Peculiarity of Enolizable Oxoesters in the Organocatalyzed Mannich-Type Addition to Cyclic N-Acyl Iminium Ions

“…In particular, chiral γ-butyrolactones having an aryl group at β-stereocenter are of considerable importance in themselves and as key precursors to the synthesis of γ-aminobutyric acid derivatives [32][33][34]. While the enantioselective introduction of the aryl moiety at the β-position has been accomplished by asymmetric conjugate addition [35][36][37], or Heck-Matsuda coupling [38], the introduction of nitrogen heterocycles remains challenging [39]. Furthermore, to the best of our knowledge, the introduction of a heteroaryl moiety into the γ-position of a δ-lactone also in a racemic fashion is unprecedented.…”

“…remains challenging [39]. Furthermore, to the best of our knowledge, the introduction of a heteroaryl moiety into the γ-position of a δ-lactone also in a racemic fashion is unprecedented.…”

Catalytic Strategies to Convert 2‐Halopyridines to 2‐Alkylpyridines

“…To date, a range of olefin coupling partners have been effectively utilized in this reaction manifold, with slight modifications based on the electronic nature of the component. Employing an iridium‐based photocatalyst and Hantszch ester as a reductant, mono‐, di‐, and tri‐substituted Michael acceptors are all effective radical trapping agents (Figure A) . Amino acid precursors can also be employed, and in relevant cases were demonstrated to proceed with varying levels of diastereoselectivity (Figure B) .…”

Carboamination of Unactivated Alkenes through Three‐Component Radical Conjugate Addition

“…Thereductiveconjugateradicaladditionofanalkylhalideto an electron deficient alkene,k nown as the Giese reaction, represents av aluable transformation in organic synthesis. [1] Along with halides, [2] amine, [3] and alcohol, [4] carboxylic acid derivatives, [5] among other compound classes,have been used as radical precursors in such additions (Scheme 1a). [6][7][8] Notably,t he Giese reaction allows for construction of quaternary carbons under mild and practical conditions.…”