Intermolecular C-H···O and C-H···X interactions in substituted spiroacenaphthylene structures

Area of Science:

• Crystallography
• Organic Chemistry
• Supramolecular Chemistry

Background:

• Spiroacenaphthylene derivatives represent a complex class of organic compounds with potential applications in materials science.
• Understanding the structure-property relationships of these molecules is crucial for designing new functional materials.
• Halogenated aromatic systems often exhibit unique intermolecular interactions that influence solid-state packing.

Purpose of the Study:

• To synthesize and characterize three novel dispiro[acenaphthylene-pyrrolo[1,2-c][1,3]thiazole-piperidine] dione derivatives.
• To elucidate the detailed three-dimensional structures of these compounds using X-ray crystallography.
• To investigate the conformational preferences and intermolecular interactions governing their crystal packing.

Main Methods:

• Single-crystal X-ray diffraction analysis was performed on three synthesized compounds.
• Conformational analysis of the piperidine, thiazolidine, and pyrrolidine rings was conducted.
• Identification and analysis of intramolecular and intermolecular interactions, including hydrogen bonding and halogen bonding, were carried out.

Main Results:

• The three compounds, featuring 2,3-dichloro-, 4-fluoro-, and 4-bromophenyl substituents, were successfully characterized.
• All structures exhibited a half-chair conformation for the piperidine ring, a twisted envelope for the thiazolidine ring, and an envelope for the pyrrolidine ring.
• Intramolecular C-H···O interactions were observed, and crystal packing was stabilized by intermolecular C-H···O and C-H···X (X=Cl, F, S, Br) interactions, forming centrosymmetric ring motifs.

Conclusions:

• The study provides a detailed structural insight into a series of halogenated dispiroacenaphthylene derivatives.
• The conformational analysis highlights the flexibility and specific spatial arrangements of the heterocyclic rings within the spirocyclic framework.
• The identified intermolecular interactions are key to understanding the crystal engineering and solid-state properties of these novel compounds.