Syntheses and crystal structures of the anhydride 4-oxatetracyclo[5.3.2.02,6.08,10]dodec-11-ene-3,5- dione and the related imide 4-(4-bromophenyl)-4- azatetracyclo[5.3.2.02,6.08,10]dodec-11-ene-3,5- dione.

The syntheses and crystal structures of the two title compounds, C11H10O3 (I) and C17H14BrNO2 (II), both containing the bicyclo[2.2.2]octene ring system, are reported here [the structure of I has been reported previously: White & Goh (2014). Private Communication (refcode HOKRIK). CCDC, Cambridge, England]. The bond lengths and angles of the bicyclo[2.2.2]octene ring system are similar for both structures. The imide functional group of II features carbonyl C O bond lengths of 1.209 (2) and 1.210 (2) A˚, with C—N bond lengths of 1.393 (2) and 1.397 (2) A˚ . The five-membered imide ring is nearly planar, and it is positioned exo relative to the alkene bridgehead carbon atoms of the bicyclo[2.2.2]octene ring system. Non-covalent interactions present in the crystal structure of II include a number of C—H. . . O interactions. The extended structure of II also features C—H. . .O hydrogen bonds as well as C—H and lone pair– interactions, which combine together to create supramolecular sheets. [ABSTRACT FROM AUTHOR]