External-Photocatalyst-Free Visible-Light-Mediated Synthesis of Indolizines

Angewandte Chemie - International Edition

Volumn 54, Issue 51, 2015, Pages 15545-15549

  Sahoo, Basudev ^a   Hopkinson, Matthew N ^a   Glorius, Frank ^a  

^a UNIVERSITY OF MÜNSTER   (Germany)

Author keywords

heterocyclic compounds; indolizines; photocatalysis; radicals; visible light

Indexed keywords

LIGHT SOURCES; ORGANIC COMPOUNDS; PHOTOCATALYSIS; SYNTHESIS (CHEMICAL);

CARBAMATE DERIVATIVES; ELECTRON WITHDRAWING GROUP; HETEROCYCLIC COMPOUND; INDOLIZINES; MECHANISTIC STUDIES; RADICALS; REACTION MECHANISM; VISIBLE LIGHT;

LIGHT;

EID: 84955170432     PISSN: 14337851     EISSN: 15213773     Source Type: Journal    
DOI: 10.1002/anie.201506868     Document Type: Article

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50. max=465 nm) as the irradiation source fitted with a long-pass filter at 455 nm, however, resulted in only a 15 % yield of 3 aa (GC yield, cf. 55 % GC yield in the absence of the filter). Indolizine 3 aa was formed in 48 % GC yield using the same light source with a long-pass filter at 400 nm. These results would seem to imply that the visible-light tail of the blue LEDs at wavelengths below 455 nm (and above 400 nm) is mostly responsible for the observed reactivity.
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