18042-31-4Relevant academic research and scientific papers
Asymmetric Photocatalytic C-H Functionalization of Toluene and Derivatives
Mazzarella, Daniele,Crisenza, Giacomo E. M.,Melchiorre, Paolo
, p. 8439 - 8443 (2018)
Reported herein is a visible-light-mediated organocatalytic direct C-H functionalization of toluene derivatives to afford enantioenriched β-benzylated aldehydes from the corresponding enals. The process combines the oxidative power of a chiral excited-state iminium ion and the basic nature of its counteranion to trigger the generation of benzylic radicals by means of a sequential multisite proton-coupled electron transfer mechanism. This study shows that feedstock chemicals generally used as solvents, such as toluene and xylene derivatives, can be used as substrates for making chiral molecules with high enantioselectivity.
Photo-Organocatalytic Enantioselective Radical Cascade Reactions of Unactivated Olefins
Bonilla, Pablo,Rey, Yannick P.,Holden, Catherine M.,Melchiorre, Paolo
supporting information, p. 12819 - 12823 (2018/09/20)
Radical cascade processes are invaluable for their ability to rapidly construct complex chiral molecules from simple substrates. However, implementing catalytic asymmetric variants is difficult. Reported herein is a visible-light-mediated organocatalytic strategy that exploits the excited-state reactivity of chiral iminium ions to trigger radical cascade reactions with high enantioselectivity. By combining two sequential radical-based bond-forming events, the method converts unactivated olefins and α,β-unsaturated aldehydes into chiral adducts in a single step. The implementation of an asymmetric three-component radical cascade further demonstrates the complexity-generating power of this photochemical strategy.
