Aminosalicylic Acid Hydrazone Dioxomolybdenum(VI) Complex: Synthesis, Spectral Characterization and Application as a Green Homogeneous Lewis Acid Catalyst for the One-Pot Three-Component Synthesis of 2-Amino-3-Cyano-4H-Pyrans

Controlled Modification of Triaminoguanidine-Based μ3 Ligands in Multinuclear [VIVO]/[VVO2] Complexes and Their Catalytic Potential in the Synthesis of 2-Amino-3-cyano-4H-pyrans/4H-chromenes

“…The catalytic efficiency of dioxidovanadium­(V) complexes reported here has been compared with other catalytic results reported from the previous studies, − and the possible outcomes are presented in Table . The findings indicate that the dioxidovanadium­(V) complexes employed in this process have benefits over the majority of catalysts documented in the literature with regard to an easy setup process, a quicker reaction period, greater reusability, a clean reaction, increased reaction rate advancement, and a higher product yield.…”

“…This reaction was steered according to a conventional strategy . A mixture of malononitrile (0.100 g, 1.5 mmol), dimedone (0.211 g, 1.5 mmol), benzaldehyde (0.160 g, 1.5 mmol), and 5 (0.004 g, 6.35 × 10 –3 mmol) (as a typical catalyst) was taken in a flask.…”

“…This reaction was steered according to a conventional strategy. 41 A mixture of malononitrile (0.100 g, 1.5 mmol), dimedone (0.211 g, 1.5 mmol), benzaldehyde (0.160 g, 1.5 mmol), and 5 (0.004 g, 6.35 × 10 −3 mmol) (as a typical catalyst) was taken in a flask. Addition of 5 mL of EtOH and refluxing of the resulting solution in an oil bath resulted in precipitation of a white solid within a few minutes.…”

“…Such diverse biological, pharmaceutical, and medicinal uses of pyran-annulated heterocyclic molecules have drawn the attention of chemists to develop novel synthetic ways for the preparations of these medicinally important pyran derivatives. Therefore, several approaches have been described earlier; however, the most effective and straightforward methods are those that involve the one-pot, three-component reaction between aryl aldehyde, malononitrile, and C–H-activated compounds (like dimedone, 1,3-cyclohexanedione, and barbituric acid) using different homogeneous/heterogeneous catalysts. − Although the catalytic multicomponent synthesis of pyrans reported in the literature has its own advantages, it still has some drawbacks including extended reaction periods, unfavorable reaction conditions, costly catalyst, high requirement of catalyst, and formation of side products. However, searching for a more efficient, green, highly economical, and high-yielding route, which requires a low catalyst amount, remains a valid exercise.…”

Polymer Supported Nitrogen‐Bridged Symmetrical Binuclear Dioxidomolybdenum(VI) Complexes and Their Homogeneous Analogues as Potential Catalysts for Efficient Synthesis of 2‐Amino‐3‐Cyano‐4H‐Chromenes/Pyrans

“…From the literature survey, it has been found that there are several methods already reported for the synthesis of ACCs, for examples, Lewis acid-base based catalysts, organo-catalysts, homogeneous as well as heterogeneous catalysts such as DBU, [33] L-proline, [34] piperazine, [35] triethylamine, [36] K 2 CO 3 , [37] triethylammonium hydrogen sulfate, [38] BF 3 .SiO 2 , [39] 2,2,2-trifluoroethanol (TFE), [40] choline chloride urea, [41] RGO-SO 3 H, [42] [bmim]OH, [43] CoCeO 2 NPs, [44] ZIF@ZnTiO 3 , [45] thiourea dioxide [46] etc. Only recently study on the multicomponent synthesis of ACCs using a homogeneous cis-[Mo VI O 2 ] complex as catalyst has been reported in the literature, [47] while two other studies have considered heterogeneous Fe 3 O 4 -supported molybdenum nano catalysts for this synthesis. [48,49] Zhang et al reported the syntheses and structures of monoas well as bi-nuclear cis-[Mo VI O 2 ] complexes of ligand (iii) (Scheme 1).…”