Abstract
A selective one-pot synthesis of carbonyl-containing N-heterocyclic compounds has been developed using a carbonylative Sonogashira/cyclisation sequence. Various catalytic protocols were studied (CO pressure, temperature, catalyst identity, base and substrate/catalyst ratio) with the objective of obtaining selectively either indoxyl or 4-quinolone products. The origin of the selectivity toward the 5- or 6-membered ring compounds was explained through the respective role of the various catalytic species involved, whether they are organic or metallic. The non-cyclic common intermediate was selectively prepared using [PdCl2(dppp)] as catalyst. By using a two-step multi-catalysis, i.e. {[Pd]+HNEt2}, 4-quinolones were obtained whereas with a tandem catalysis, i.e. {[Pd]/PR3}, indoxyls were synthesised.
Original language | English (US) |
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Pages (from-to) | 125-132 |
Number of pages | 8 |
Journal | Applied Catalysis A: General |
Volume | 369 |
Issue number | 1-2 |
DOIs | |
State | Published - Nov 15 2009 |
Externally published | Yes |
Bibliographical note
Funding Information:MG and AB are grateful to the National Agency of Research for financial support (No. ANR-07-BLAN-0167-01/02 ).
Keywords
- 4-Quinolones
- Carbonylative Sonogashira
- Indoxyls
- One-pot synthesis
- Palladium catalysis
ASJC Scopus subject areas
- Catalysis
- Process Chemistry and Technology