Zn(L-proline)2: An efficient and reusable organocatalyst for the synthesis of polyfunctionally substituted pyrans and 2-amino-4-aryl-8-oxo-4,8-dihydropyrano[3,2-b]pyran derivatives

Abstract

Efficient synthesis of non-annulated 2-amino-4H-pyrans and 2-amino-8-oxo-4,8-dihydropyrano[3,2-b]pyran derivatives, which are biologically relevant heterocycles is achieved, utilizing a domino three-component reaction of ethyl acetoacetate or kojic acid with aromatic aldehydes and malononitrile catalyzed by Zn(L-proline)2 as reusable organometallic catalyst. The process exhibits high atom economy, short reaction time, simple work up, high yields and environmentally friendly nature. Excellent yields of the targeted molecules have been obtained.

Friedländer, Knoevenagel, and Michael Reactions Employing the Same MOF: Synthesis, Structure, and Heterogeneous Catalytic Studies of ([Zn(1,4-NDCA)(3-BPDB)0.5]·(DMF)(MeOH) and [Cd4(1,4-NDCA)4(3-BPDB)4]·2(DMF)

“…The KM reactions were investigated using MOFs and other compounds (Table ). As can be noted, the present compounds have comparable catalytic activity as reported earlier. − …”

“…4H-Pyran derivatives can be synthesized using a three-component condensation of an aldehyde, malononitrile, and ethylacetoacetate (Scheme ). The three-component condensation was shown to be catalyzed by Lewis base catalysts. − In the present study, the compounds ( I and II ) contain the Lewis base centers (−CN–NC−), which may aid in the Lewis base catalysis.…”

Theoretical DFT study of Cannizzaro reaction mechanism: A mini perspective

“…Kinetics is an important aspect of any reaction; especially for organic reactions [11][12][13][14][15]. The kinetics give us important data about the reaction.…”