Radical Arene Addition vs Radical Reduction: Why Organometal Hydride Chain Reactions Stop and How To Make Them Go

The Journal of Organic Chemistry
Vincent W Bowry, Chryssostomos Chatgilialoglu

Abstract

Nonideal kinetic chain analysis was used to examine the kinetic limitations of free-radical synthesis. Homolytic aromatic substitution (HAS: ArH + R• → ArR + H•) occurs in a chain-terminating side reaction to the tributyltin hydride ( SnH) reduction chain (RX + SnH + ( i•)cat. → RH + SnX). Kinetic modeling of premixed and slow reagent addition reactions have clarified the mechanisms of SM HAS, with the azo initiator ( iNN i) acting not only as radical source but also (as an H• acceptor) as the redox catalyst for aromatization, and/or as a postaddition oxidant. Refractory halides and other hitherto baffling anomalies may arise from the build up of ipso (rather than ortho)-cycloadduct radicals in the steady-state radical population. The implications of these findings for "tin-free" radical chains (and emerging photoredox methods) are considered via historical and recent examples of the effects of chain-degrading radical transfer (to substrate, product, solvent, initiator, and/or reagent ligands) on the reagent's chain.

References

Apr 27, 2001·Chemistry : a European Journal·A Studer
Jul 18, 2001·Journal of the American Chemical Society·C FerreriC Chatgilialoglu
Mar 27, 2003·Journal of the American Chemical Society·Chryssostomos ChatgilialogluQuinto G Mulazzani
May 8, 2003·Journal of the American Chemical Society·Armido StuderJohn C Walton
Dec 25, 2003·Angewandte Chemie·Athelstan L J BeckwithJohn M D Storey
Feb 11, 2004·Organic & Biomolecular Chemistry·W Russell BowmanMark B Schilling
Feb 14, 2006·Organic Letters·M-Lluïsa BennasarFrancesc Ferrando
Jun 6, 2006·The Journal of Organic Chemistry·Maria Luisa NavacchiaPier Carlo Montevecchi
Oct 19, 2006·Journal of the American Chemical Society·Dennis P Curran, Adam I Keller
May 11, 2007·Accounts of Chemical Research·David CrichMitesh Patel
Jan 25, 2008·Chemical Society Reviews·W Russell Bowman, John M D Storey
Mar 9, 2010·Journal of the American Chemical Society·Marie-Hélène LarraufieLouis Fensterbank
Feb 2, 2011·The Journal of Organic Chemistry·Ching Yeh LinMichelle L Coote
Sep 3, 2011·Journal of the American Chemical Society·Achim BruchDennis P Curran
Oct 26, 2012·The Journal of Organic Chemistry·Elizabeth L TysonTehshik P Yoon
Mar 21, 2013·Chemical Reviews·Christopher K PrierDavid W C MacMillan
Jun 15, 2013·Beilstein Journal of Organic Chemistry·Roy T McBurney, John C Walton
Apr 9, 2016·Organic & Biomolecular Chemistry·Michael Gurry, Fawaz Aldabbagh
Jun 1, 2016·Journal of the American Chemical Society·Dennis P Curran, Timothy R McFadden
Apr 22, 2017·Nature Chemistry·Michael A Tarselli
May 10, 2017·Proceedings. Mathematical, Physical, and Engineering Sciences·Béatrice Quiclet-Sire, Samir Z Zard

❮ Previous
Next ❯

Citations

Jul 27, 2020·Chemistry : a European Journal·Joshua W M MacMillanSaurabh S Chitnis

❮ Previous
Next ❯

Related Concepts

Trending Feeds

COVID-19

Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Blastomycosis

Blastomycosis fungal infections spread through inhaling Blastomyces dermatitidis spores. Discover the latest research on blastomycosis fungal infections here.

Nuclear Pore Complex in ALS/FTD

Alterations in nucleocytoplasmic transport, controlled by the nuclear pore complex, may be involved in the pathomechanism underlying multiple neurodegenerative diseases including Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Here is the latest research on the nuclear pore complex in ALS and FTD.

Applications of Molecular Barcoding

The concept of molecular barcoding is that each original DNA or RNA molecule is attached to a unique sequence barcode. Sequence reads having different barcodes represent different original molecules, while sequence reads having the same barcode are results of PCR duplication from one original molecule. Discover the latest research on molecular barcoding here.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Evolution of Pluripotency

Pluripotency refers to the ability of a cell to develop into three primary germ cell layers of the embryo. This feed focuses on the mechanisms that underlie the evolution of pluripotency. Here is the latest research.

Position Effect Variegation

Position Effect Variagation occurs when a gene is inactivated due to its positioning near heterochromatic regions within a chromosome. Discover the latest research on Position Effect Variagation here.

STING Receptor Agonists

Stimulator of IFN genes (STING) are a group of transmembrane proteins that are involved in the induction of type I interferon that is important in the innate immune response. The stimulation of STING has been an active area of research in the treatment of cancer and infectious diseases. Here is the latest research on STING receptor agonists.

Microbicide

Microbicides are products that can be applied to vaginal or rectal mucosal surfaces with the goal of preventing, or at least significantly reducing, the transmission of sexually transmitted infections. Here is the latest research on microbicides.