Format

Send to

Choose Destination
See comment in PubMed Commons below
Angew Chem Int Ed Engl. 2014 Sep 22;53(39):10515-9. doi: 10.1002/anie.201405178. Epub 2014 Aug 14.

Conjugate umpolung of β,β-disubstituted enals by dual catalysis with an N-heterocyclic carbene and a Brønsted acid: facile construction of contiguous quaternary stereocenters.

Author information

1
Organisch-Chemisches Institut, NRW Graduate School of Chemistry, Westfälische Wilhelms-Universität Münster, Corrensstrasse 40, 48149 Münster (Germany) http://www.uni-muenster.de/Chemie.oc/glorius/index.html.

Abstract

A sterically hindered homoenolate has been generated by the NHC-catalyzed conjugate umpolung of β,β-disubstituted enals and successfully employed in a facile stereoselective annulation with isatins. The strategy provides efficient access to spirocyclic oxindoles bearing two highly congested contiguous quaternary carbon centers. The use of a Brønsted acid cocatalyst was found to be crucial for guaranteeing both excellent reactivity and high stereoselectivity.

KEYWORDS:

carbenes; dual catalysis; quaternary centers; spiro compounds; umpolung

PMID:
25124301
DOI:
10.1002/anie.201405178
[Indexed for MEDLINE]
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Wiley
    Loading ...
    Support Center