In the title compound, C35H36N2O5·0.5C 4H10O, the asymmetric unit contains one bicyclo-[3.3.1]nonane mol-ecule and a half-occupancy diethyl ether solvent with the O atom lying on a crystallographic inversion center. Two intra-molecular N- H⋯O hydrogen bonds generate S(6) ring motifs. The bicyclo-[3.3.1]nonane ring system adopts a chair-boat conformation. In the crystal structure, the mol-ecules are linked by weak inter-molecular C- H⋯N hydro-gen bonds into chains along the b axis; additional stabilization is provide by C- H⋯π inter-actions.