Diastereoselective intramolecular alpha-amidoalkylation reactions of L-DOPA derivatives. Asymmetric synthesis of pyrrolo[2,1-a]isoquinolines.
[reaction: see text] Stereocontrolled intramolecular alpha-amidoalkylation reactions of L-DOPA-derived succinimides have been studied. Addition of MeLi to nonracemic succinimides 9a-d yields oxoamides, which are cyclized upon treatment with Lewis or protic acids to afford (5S,10bS)-trans 11 or (5S,10bR)-cis 12pyrroloisoquinolines with variable diastereoselectivities, but with high enantiomerical purities (ee 99%).
García
Eva
E
Departamento de Química Orgánica II, Facultad de Ciencia y Tecnología, Universidad del País Vasco/Euskal Herriko Unibertsitatea, Apdo 644, 48080 Bilbao, Spain.
Arrasate
Sonia
S
Lete
Esther
E
Sotomayor
Nuria
N