Stereoselective C9 arylation and vinylation of Cinchona alkaloids.
A simple and efficient method for the highly stereoselective C-9 arylation and vinylation of Cinchona alkaloids was developed. Both 9S- and 9R-chloroquinine with PhMgBr yielded 9S-phenylquinine (X-ray structure). The reactions with various aryl and vinyl Grignard reagents resulted in the series of 9S-aryl and vinyl alkaloid derivatives. The stereochemical outcome was rationalized by coordination of the magnesium atom to the quinuclidine nitrogen, thus directing the nucleophilic attack at the C-9 stereogenic center.
Boratyński
Przemysław J
PJ
Department of Organic Chemistry, Faculty of Chemistry, Wrocław University of Technology, 50-370 Wrocław, Poland.
Turowska-Tyrk
Ilona
I
Skarzewski
Jacek
J
D002930:Cinchona Alkaloids / Q000737:chemistry*; D018360:Crystallography, X-Ray; D006843:Hydrocarbons, Chlorinated / Q000737:chemistry*; D008968:Molecular Conformation; D015394:Molecular Structure; D013237:Stereoisomerism; D014753:Vinyl Compounds / Q000737:chemistry*
D002930:Cinchona Alkaloids; D006843:Hydrocarbons, Chlorinated; D014753:Vinyl Compounds