A series of new enantiomerically pure (S)-3-hydroxy-3phenyl-3,4-dihydroquinolin-2(1H)-ones was prepared in good yields according to a two-step synthesis using a benzylation of the sodium enolate of the (2S,5S)-cis-2-tert-butyl-5-phenyl-1,3-dioxolan-4-one with substituted o-nitrobenzyl bromides followed by reduction of the nitro group to amine with concomitant intramolecular aminolysis of the dioxolanone ring.

Enantioselective Synthesis of (S)-3-Hydroxy-3-phenyl-3,4-dihydroquinolin--2(1H)-one Ring System. -A practical two-step synthesis of target compounds (IV) uses dioxolanone (II), derived from (S)-mandelic acid, as the chiral source. The intermediate products (III) are obtained as single isomers and no racemization is observed in the process. -(BLAY, G.; CARDONA, L.; TORRES, L.; PEDRO*, J. R.; Synthesis 2007, 1, 108-112; Dep. Quim. Org.,

Die Reaktion von Nitrosafrol (Ia) mit NBS liefert die Verbindung (IIIa) [daneben Spuren der Produkte (IIc) + (IId)]; in Gegenwart von Tetrabutylammoniumbromid wird jedoch das Dibromid (IIa) erhalten, das auch bei der Bromierung von (Ia) mit Br, entsteht.