| Literature DB >> 20104898 |
Venkata Jaganmohan Reddy1, Christopher J Douglas.
Abstract
The first asymmetric cyanoamidation with synthetically useful enantioselectivity (ee up to 99%) to produce 3,3-disubstituted oxindoles is reported. Palladium catalysts with chiral phosphoramidite ligands activate the cyanoformamide C-CN bond, which is subsequently functionalized with a tethered alkene to give all-carbon quaternary stereocenters. The use of the N,N-(i-Pr)(2) derivative of octahydro-MonoPhos allowed the production of oxindoles with high enantioselectivities. Cyanoformamides bearing free N-H groups are now tolerated, potentially allowing protecting-group-free synthesis. Oxindole products of cyanoamidation are rapidly transformed into (+)-horsfiline, (-)-coerulescine, and (-)-esermethole.Entities:
Year: 2010 PMID: 20104898 DOI: 10.1021/ol902949d
Source DB: PubMed Journal: Org Lett ISSN: 1523-7052 Impact factor: 6.005