Rhodium(II) acetate catalyzed domino reactions of bis-diazo compounds afford epoxy-
and epithio-bridged heterocycle-fused quinolizinone systems in a stereoselective manner.
The presence of an acceptor diazo functionality leads to a selective intermolecular
X–H insertion reaction in a chemoselective manner, and the acceptor/acceptor diazo
functionality subsequently participates in the formation of isomünchnone/thioisomünchnone
1,3-dipoles followed by intramolecular cycloaddition in a diastereoselective manner.
This domino reaction is capable of constructing epoxy- and epithio-bridged heterocycle-fused
quinolizinone ring systems with four stereogenic centers. The Brønsted acid induced
reactions of oxa-bridged tricyclic compounds furnish ring-opened alcohol products
in a regioselective manner.
Key words
bis-diazo compounds - domino reactions - diastereoselectivity - X–H insertion - isomünchnones
- rhodium(II) acetate