Crystal Structure of 3,3′-Ethanediylidenebis(1-ethylindoline-2-one): An Unexpected Byproduct in N-Ethylation of Isatin in Tetrahydrofurane

摘要

The title compound 3,3′-ethanediylidenebis(1-ethylindoline-2-one) was isolated as a byproduct through the reaction of isatin and sodium hydride with iodoethane in tetrahydrofurane. It crystallizes in the space group P2₁/c (#14) with the cell parameters a = 8.7451(9)Å, b = 15.1964(13)Å, c = 6.9425(6)Å, β = 113.561(2)°, Z = 2, and V = 845.70(14)Å3. The 3,3′-ethanediylidenebis(indoline-2-one) core is planar, adopting an s-trans conformation with regard to the ethanediylidene moiety. The crystal structure is stabilized by intermolecular C=O…HC and N…HC hydrogen bonds as well as by π-π interactions.