2,4-Bis(4-eth­oxy­phen­yl)-1-methyl-3-aza­bicyclo­[3.3.1]nonan-9-one

In the title compound, C(25)H(30)NO(3), a crystallographic mirror plane bis­ects the mol­ecule. Although it is a positional isomer of 2,4-bis(4-eth­oxy­phen­yl)-7-methyl-3-aza­bicyclo­[3.3.1]non­an-9-one [C(25)H(31)NO(3), M (r) = 393.51; Park et al. (2012c ▶). Acta Cryst. E68, o779–780], its mol­ecular weight is 392.50 due to the 50:50 ratio of the methyl group at bridgehead C atoms. However, the title compound exists in the same twin-chair conformation as its 7-methyl isomer. Also, the 4-eth­oxy­phenyl groups are equatorially oriented on the bicycle as in its isomer. In the title compound, the cyclo­hexanone ring deviates from an ideal chair (total puckering amplitude Q (T) = 0.5390 Å) and the piperidone ring is closer to an ideal chair (Q (T) = 0.6064 Å). These Q (T) values are very similar to those of its isomer. Even though a center of symmetry passes through the 7-methyl analog, the benzene rings are oriented 26.11 (3)° with respect to each other, whereas the orientation is 53.10 (3)° for the title compound. The title compound exhibits inter­molecular N—H⋯O inter­actions [H⋯A = 2.25 (2) Å, versus 2.26 (2) Å for the analog].