One‐pot Three‐component Route for the Synthesis of Functionalized 4H‐chromenes Catalyzed by ZrOCl₂·8H₂O in Water

Abstract

An efficient method for the synthesis of functionalized 4H‐chromenes via a one‐pot three‐component condensation reaction of a 2‐hydroxybenzaldehyde with an active methylene compound and a carbon‐based nucleophile in the presence of a catalytic amount of ZrOCl2·8H2O in water under thermal condition has been described. High yields, simple work‐up procedure, performing reactions in water and synthesis of complex molecules with a one‐pot procedure are the main advantages of this procedure. In addition, the structure of the product from the condensation of salicylaldehyde, 2‐naphthol, and dimedone was confirmed by X‐ray crystallography.

Recent Advances of Three‐component Reactions of Simple Indoles

“…On the other hand, isocyanate 17.3 [24] and carbonyl 17.4 [25a–f] could also act as acceptors. The use of novel catalysts, such as Fe 3 O 4 @SiO 2 @D‐NHCS‐Tr, [25b] heterogeneous amberlite IRA‐400 Cl, [25d] TH catalyst (an acid hydrolysate of tendons), [25e] have been reported recently.…”

Green and efficient one-pot three-component synthesis of novel drug-like furo[2,3-d]pyrimidines as potential active site inhibitors and putative allosteric hotspots modulators of both SARS-CoV-2 MPro and PLPro

“…Zirconium IV oxychloride octahydrate (ZrOCl 2 •8H 2 O), as an available, low-cost, easy handling, and moisture-stable catalyst with highly coordinating ability, has attracted the attention in the organic synthetic community. [23] In the past two decades, the mentioned green catalyst has been used frequently in various organic transformations, especially heterocyclic ones, including syntheses of 4 H -chromenes, [24] pyrimido [4] , [5] , [6] , [7] , [8] , [9] , [10] , [11] , [12] , [13] , [14] , [15] , [16] , [17] , [18] , [19] , [20] , [21] , [22] , [23] , [24] , [25] , [26] , [27] , [28] , [29] , [30] , [31] , [32] , [33] , [34] , [35] , [36] , [37] , [38] , [39] , [40] , [41] , [42] , [43] , [44] , [45] , [46] , [47] , [48] , [49] , [50] , [51] , [52] , [53] , [54] , [55] , [56] , [57] pyrimidinones, [25] dibenzo[ b , i ]xanthene-tetraones, [26] , [1] , [3] oxazino [5] , [6] ,…”