Catalysis of Radical Cyclizations from Alkyl Iodides under H2: Evidence for Electron Transfer from [CpV(CO)3H].
J Am Chem Soc
; 140(13): 4512-4516, 2018 04 04.
Article
em En
| MEDLINE
| ID: mdl-29543448
ABSTRACT
Radical cyclizations are most often achieved with Bu3SnH in the presence of a radical initiator, but environmental considerations demand that alternative reagents be developed-ones that can serve as a synthetic equivalent to the hydrogen atom. We have revisited [CpV(CO)3H]-, a known replacement for Bu3SnH, and found that it can be used catalytically under H2 in the presence of a base. We have carried out tin-free catalytic radical cyclizations of alkyl iodide substrates. The reactions are atom-efficient, and the conditions are mild, with broad tolerance for functional groups. We have, for example, achieved the first 5-exo radical cyclization involving attack onto a vinyl chloride. We suggest that the radicals are generated by an initial electron transfer.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Cloreto de Vinil
/
Hidrogênio
/
Iodetos
Idioma:
En
Ano de publicação:
2018
Tipo de documento:
Article