title: Organocatalytic route to dihydrocoumarins and dihydroquinolinones in all stereochemical configurations.
abstract: A straightforward stereodivergent route to dihydrocoumarins and dihydroquinolinones based on cinchona alkaloid catalyzed addition reactions of monothiomalonates (MTMs) to functionalized nitroolefins followed by deprotection and chemoselective cyclization has been developed. The synthesis proceeds under mild conditions and yields heterocycles with adjacent quaternary and tertiary stereogenic centers in very high yields and stereoselectivities. Moreover, full control over the relative and absolute configuration is achieved by the use of (pseudo)enantiomeric catalysts and the difference in reactivity of thioester versus oxoester moieties.
authors.affiliation: ETH Zürich , Laboratory for Organic Chemistry, Vladimir-Prelog-Weg 3, 8093 Zürich, Switzerland.
authors.forename: Oliver D
authors.initials: OD
authors.lastname: Engl
authors.forename: Sven P
authors.initials: SP
authors.lastname: Fritz
authors.forename: Alexander
authors.initials: A
authors.lastname: Käslin
authors.forename: Helma
authors.initials: H
authors.lastname: Wennemers
mesh_terms: D002384:Catalysis; D002930:Cinchona Alkaloids / Q000737:chemistry*; D003374:Coumarins / Q000138:chemical synthesis* / Q000737:chemistry; D003500:Cyclization; D008314:Malonates / Q000737:chemistry; D015394:Molecular Structure; D015363:Quinolones / Q000138:chemical synthesis / Q000737:chemistry; D013237:Stereoisomerism
chemical_list: D002930:Cinchona Alkaloids; D003374:Coumarins; D008314:Malonates; D015363:Quinolones