Novel heterocycles. 8. Fused isoquinolines derived from the reaction of homophthalic anhydride with cyclic imino ethers

Homophthalic anhydride and cyclic imino ethers react to produce fused isoquinolines 6–9. In the case of 2‐ethoxy‐2‐oxazoline, a second compound whose structure is believed to be the spiro compound 10 was also isolated. Spectral data for these type systems are discussed.