New Approach to the Detection of Short-Lived Radical Intermediates.
J Am Chem Soc
; 144(35): 15969-15976, 2022 09 07.
Article
em En
| MEDLINE
| ID: mdl-36001076
ABSTRACT
We report a new general method for trapping short-lived radicals, based on a homolytic substitution reaction SH2'. This departure from conventional radical trapping by addition or radical-radical cross-coupling results in high sensitivity, detailed structural information, and general applicability of the new approach. The radical traps in this method are terminal alkenes possessing a nitroxide leaving group (e.g., allyl-TEMPO derivatives). The trapping process thus yields stable products which can be stored and subsequently analyzed by mass spectrometry (MS) supported by well-established techniques such as isotope exchange, tandem MS, and high-performance liquid chromatography-MS. The new method was applied to a range of model radical reactions in both liquid and gas phases including a photoredox-catalyzed thiol-ene reaction and alkene ozonolysis. An unprecedented range of radical intermediates was observed in complex reaction mixtures, offering new mechanistic insights. Gas-phase radicals can be detected at concentrations relevant to atmospheric chemistry.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Alcenos
/
Espectrometria de Massas em Tandem
Tipo de estudo:
Diagnostic_studies
Idioma:
En
Revista:
J Am Chem Soc
Ano de publicação:
2022
Tipo de documento:
Article
País de afiliação:
Reino Unido