Dimethyl 2-[23-oxo-22,24-diphenyl-8,11,14-trioxa-25-azatetracyclo[19.3.1.02,7.015,20]pentacosa-2,4,6,15(20),16,18-hexaen-25-yl]but-2-enedioate

The title compound, C39H37NO8, is a product of the Michael addition of the cyclic secondary amine subunit of aza-14-crown-4 ether to dimethyl acetylenedicarboxylate. The piperidinone ring exhibits a distorted chair conformation and the dimethyl acetylenedicarboxylate fragment has a cis configuration with a dihedral angle of 56.61 (5)° between the two carboxylate groups. The crystal packing is stabilized by the weak C—H...O hydrogen bonds