Visible-light-induced intramolecular charge transfer in the radical spirocyclisation of indole-tethered ynones.
Chem Sci
; 11(5): 1353-1360, 2019 Dec 13.
Article
in En
| MEDLINE
| ID: mdl-34123259
ABSTRACT
Indole-tethered ynones form an intramolecular electron donor-acceptor complex that can undergo visible-light-induced charge transfer to promote thiyl radical generation from thiols. This initiates a novel radical chain sequence, based on dearomatising spirocyclisation with concomitant C-S bond formation. Sulfur-containing spirocycles are formed in high yields using this simple and mild synthetic protocol, in which neither transition metal catalysts nor photocatalysts are required. The proposed mechanism is supported by various mechanistic studies, and the unusual radical initiation mode represents only the second report of the use of an intramolecular electron donor-acceptor complex in synthesis.
Full text:
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Collection:
01-internacional
Database:
MEDLINE
Language:
En
Journal:
Chem Sci
Year:
2019
Document type:
Article