[3+2] Cycloaddition Reaction for the Stereoselective Synthesis of a New Spirooxindole Compound Grafted Imidazo[2,1-<em>b</em>]thiazole Scaffold: Crystal Structure and Computational Study

A new spirooxindole hybrid engrafted imidazo[2,1-<i>b</i>]thiazole core structure was designed and achieved via [3+2] cycloaddition reaction approach. One multi-component reaction between the ethylene derivative based imidazo[2,1-<i>b</i>]thiazole scaffold with 6-Cl-isatin an...

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Bibliographic Details
Main Authors: Mezna Saleh Altowyan, Saied M. Soliman, Matti Haukka, Nora Hamad Al-Shaalan, Aminah A. Alkharboush, Assem Barakat
Format: Article
Language:English
Published: MDPI AG 2021-12-01
Series:Crystals
Subjects:
Online Access:https://www.mdpi.com/2073-4352/12/1/5
Description
Summary:A new spirooxindole hybrid engrafted imidazo[2,1-<i>b</i>]thiazole core structure was designed and achieved via [3+2] cycloaddition reaction approach. One multi-component reaction between the ethylene derivative based imidazo[2,1-<i>b</i>]thiazole scaffold with 6-Cl-isatin and the secondary amine under heat conditions afforded the desired compound in a stereoselective manner. The relative absolute configuration was assigned based on single-crystal X-ray diffraction analysis. Hirshfeld calculations for <b>4</b> revealed the importance of the H…H (36.8%), H…C (22.9%), Cl…H (10.4%) and S…H (6.6%), as well as the O…H (4.7%), N…H (5.3%), Cl…C (1.6%), Cl…O (1.0%) and N…O (0.5%) contacts in the crystal stability. DFT calculations showed excellent straight-line correlations (R<sup>2</sup> = 0.9776–0.9962) between the calculated and experimental geometric parameters. The compound has polar nature (3.1664 Debye). TD-DFT and GIAO calculations were used to assign and correlate the experimental UV-Vis and NMR spectra, respectively.
ISSN:2073-4352