Synthesis of the core ring system of the stemona alkaloids by cascade condensation, cyclization, intramolecular cycloaddition.
نویسندگان
چکیده
Condensation of an aldehyde with an α-amino-ester, followed by a tandem process involving cyclization to a seven-membered ring, deprotonation to an intermediate azomethine ylide and intramolecular dipolar cycloaddition gave tricyclic products related to stenine and neostenine.
منابع مشابه
Synthesis of fused tricyclic amines unsubstituted at the ring-junction positions by a cascade condensation, cyclization, cycloaddition then decarbonylation strategy
Heating aldehydes that contain a protected hydroxymethyl group, a tethered alkyl chloride and a tethered alkenyl group at the α-position of the aldehyde with an amine sets up a cascade (tandem) reaction sequence involving condensation to an intermediate imine, then cyclization and formation of an intermediate azomethine ylide and then intramolecular dipolar cycloaddition. The fused tricyclic pr...
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ورودعنوان ژورنال:
- Organic & biomolecular chemistry
دوره 8 20 شماره
صفحات -
تاریخ انتشار 2010