Syntheses and crystal structures of the anhydride 4-oxa-tetra-cyclo-[5.3.2.0.0]dodec-11-ene-3,5-dione and the related imide 4-(4-bromo-phen-yl)-4-aza-tetra-cyclo-[5.3.2.0.0]dodec-11-ene-3,5-dione.

The syntheses and crystal structures of the two title compounds, CHO () and CHBrNO (), both containing the bi-cyclo-[2.2.2]octene ring system, are reported here [the structure of has been reported previously: White & Goh (2014 ▸).