Details
| Original language | English |
|---|---|
| Pages (from-to) | 6450-6456 |
| Number of pages | 7 |
| Journal | Tetrahedron |
| Volume | 66 |
| Issue number | 33 |
| Publication status | Published - 6 May 2010 |
Abstract
In the present work the stereocontrolled palladium-catalysed umpolung allylation of aldehydes is described. Allyl acetates are in situ transformed into the corresponding allyl boronates, which directly react with aldehydes. The question of stereocontrol is raised by employing (a) chiral boronating agents (reagent control) and by (b) utilising chiral aldehydes (substrate control). These studies reveal that the approach based on substrate control is superior to the former one with respect to yields and stereoselectivity. Remarkably, this umpolung protocol often yields the 4,5-syn products in high selectivity, which is unprecedented for direct crotylations.
Keywords
- Aldehydes, Allylation, Catalysis, Palladium, Umpolung
ASJC Scopus subject areas
- Biochemistry, Genetics and Molecular Biology(all)
- Biochemistry
- Pharmacology, Toxicology and Pharmaceutics(all)
- Drug Discovery
- Chemistry(all)
- Organic Chemistry
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In: Tetrahedron, Vol. 66, No. 33, 06.05.2010, p. 6450-6456.
Research output: Contribution to journal › Article › Research › peer review
}
TY - JOUR
T1 - Stereocontrolled palladium-catalysed umpolung allylation of aldehydes with allyl acetates
AU - Vogt, Monika
AU - Ceylan, Sascha
AU - Kirschning, Andreas
N1 - Funding information: The work was funded by the Fonds der Chemischen Industrie .
PY - 2010/5/6
Y1 - 2010/5/6
N2 - In the present work the stereocontrolled palladium-catalysed umpolung allylation of aldehydes is described. Allyl acetates are in situ transformed into the corresponding allyl boronates, which directly react with aldehydes. The question of stereocontrol is raised by employing (a) chiral boronating agents (reagent control) and by (b) utilising chiral aldehydes (substrate control). These studies reveal that the approach based on substrate control is superior to the former one with respect to yields and stereoselectivity. Remarkably, this umpolung protocol often yields the 4,5-syn products in high selectivity, which is unprecedented for direct crotylations.
AB - In the present work the stereocontrolled palladium-catalysed umpolung allylation of aldehydes is described. Allyl acetates are in situ transformed into the corresponding allyl boronates, which directly react with aldehydes. The question of stereocontrol is raised by employing (a) chiral boronating agents (reagent control) and by (b) utilising chiral aldehydes (substrate control). These studies reveal that the approach based on substrate control is superior to the former one with respect to yields and stereoselectivity. Remarkably, this umpolung protocol often yields the 4,5-syn products in high selectivity, which is unprecedented for direct crotylations.
KW - Aldehydes
KW - Allylation
KW - Catalysis
KW - Palladium
KW - Umpolung
UR - http://www.scopus.com/inward/record.url?scp=77955664343&partnerID=8YFLogxK
U2 - 10.1016/j.tet.2010.04.133
DO - 10.1016/j.tet.2010.04.133
M3 - Article
AN - SCOPUS:77955664343
VL - 66
SP - 6450
EP - 6456
JO - Tetrahedron
JF - Tetrahedron
SN - 0040-4020
IS - 33
ER -