A facile, rapid, one-pot regio/stereoselective synthesis of 2-iminothiazolidin-4-ones under solvent/scavenger-free conditions

Abstract

SummaryA rapid and efficient one pot solvent/scavenger-free protocol for the synthesis of 2-iminothiazolidin-4-ones has been developed. Interestingly, the regio/stereoselective synthesis affords the regioisomeric (Z)-3-alkyl/aryl-2-(2-phenylcyclohex-2-enylimino)thiazolidin-4-one as the sole product in good yield. The selectivities observed have been rationalized based on the relative magnitude of the allylic strains developed during the course of the reaction. This is the first report wherein the impact of allylic strains in directing the regiocyclization has been noted.

One-pot, solvent-free and efficient synthesis of 2,4,6-triarylpyridines catalyzed by nano-titania-supported sulfonic acid as a novel heterogeneous nanocatalyst

“…In all cases, aromatic aldehydes with substituents carrying either electron-donating or electron-withdrawing groups reacted successfully and gave the products in good yields (Table 3). It was found that aromatic aldehydes with electron-withdrawing groups (Table 3, entries 2, 3,5,8,11,13,15) reacted faster than those with electron-donating groups (Table 3, entries 4, 6, 7, 9, 12, 16-18, 20, 21), as would be expected [24,25]. These results justified one more time the efficiency of n-TSA.…”

“…Recently, solid-supported heterogeneous catalysts have gained considerable interest in organic synthesis because of their unique properties such as high efficiency due to more surface area, more stability, reusability, low toxicity and ease of handling [3][4][5][6][7][8]. We have recently reported nano titania-supported sulfonic acid (n-TSA) [9], as an effective heterogeneous acidic nanocatalyst for the promotion of a wide range of organic reactions as for its Lewis and Bronsted acidity features.…”

The first report of deep eutectic solvent (DES) nano‐photocatalyst (n‐TiO2‐P25@TDI@DES (urea: ZnCl2)) and its application on selective oxidation of benzyl alcohols to benzaldehydes

“…These problems can be overcome by the immobilization of acids, such as sulfonic acid, on the surface of TiO 2 ‐P25 30 . Owing to the insolubility of solid acids, they could be properly stable, exhibit enhanced reusability, require moderate reaction conditions with environmentally‐friendly reactions, be easily separable and operated 31–33 . Specifically, a properly‐grafted solid catalyst could result in improved dispersibility, preventing agglomeration through steric barriers 34,35 …”

A Smart and Efficient One‐Pot Green Synthesis of Novel 1, 2, 3‐Triazolyl Pyrazoline‐/Indazolyl‐Carbothioamide Hybrids under Solvent‐Free Grinding Strategy at Room Temperature

“…In view of the above and as part of our ongoing research platform on the eco‐friendly syntheses of biologically important heterocyclic/hybrid heterocyclic compounds under solvent‐free, and aqueous conditions, herein, we report a smart and efficient green synthesis of novel 1, 2, 3‐triazolyl pyrazoline‐/indazolyl‐carbothioamide hybrids from the sequential reactions of ketones, aldehydes, hydrazine hydrate and aryl isothiocyanates under one‐pot, solvent‐free grinding strategy at room temperature.…”