Crystal structures of 2′-benzoyl-1′-(4-methylphenyl)-1,1′,2,2′,5′,6′,7′,7a′-octahydrospiro[indole-3,3′-pyrrolizin]-2-one and 2′-(4-bromobenzoyl)-1′-(2-chlorophenyl)-1,1′,2,2′,5′,6′,7′,7a′-octahydrospiro[indole-3,3′-pyrrolizin]-2-one

Abstract

The two title compounds, C28H26N2O2, (I), and C27H22BrClN2O2, (II), differ in their substituents, viz.4-methylphenyl and benzoyl rings in (I) replaced by 2-chlorophenyl and 4- bromobenzoyl, respectively, in (II). A significant difference between the two molecules is found in the deviation of the benzoyl O atom from the least-squares plane of the ring to which it is attached [0.593 (4) and 0.131 (3) Å, respectively], a fact which may be attributed to the different participation of the benzoyl O atoms as acceptors in their intermolecular C—H...O interactions. The chemical modifications in (I) and (II) do not seem to affect the type nor strength of the intermolecular N—H...N and C—H...O hydrogen bonds responsible for the two crystal structures, such that the aggregation of molecules appears similar in spite of the molecular changes.

Keywords

• crystal structure
• indoline-3,3′-pyrrolizin derivatives
• hydrogen bonding