By Formation of Three Bonds from Atom Fragments

By Formation of Three Bonds from [3+2+1] Atom Fragments 

The reaction of l-cyanomethylene-6,7-dimethoxy-l,2,3,4-tetrahydro-quinoline with 35% aqueous formaldehyde in the presence ofl N NaOH at 65°C afforded [l,3]oxazino[4,3-a]isoquinoline (100) (73JHC435). 

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