A green and one-pot synthesis of benzo[g]chromene derivatives through a multi-component reaction catalyzed by lipase

Abstract

The synthesis of benzo[g]chromene derivatives through a multi-component reaction catalyzed by lipase was reported in the first time. This novel efficient method has the advantages of environmental friendliness, high yield and simple work-up.

An efficient condensation of substituted salicylaldehyde and malononitrile catalyzed by lipase under microwave irradiation

“…These results indicated that salicylaldehyde might be reacted with malononitrile which binds to the oxyanion hole in the lipase firstly. The catalytic proficiency ((k app cat /K app M )/k non 35 was much lower than 10 8 which demonstrated that the substrates in this reaction was not the native substrates of lipase [34]. According to the previous reports [32 -36], lipase can catalyze the Michael addition and Knoevenagel condensation in the domino reactions.…”

“…2- 35 Iminochromene appears as a ubiquitous structural motif in many heterocyclic compounds. Synthetic analogues were developed over the years, some of them displaying extensive bioactivities, such as antifungal and antimicrobial activity [22][23].…”

“…The condensation of salicylaldehyde and malononitrile was faster in protic/polar solvents than in nonprotic/nonpolar solvents presumably. The possible explanation might be that protic/polar solvent can enhance the stabilization of charged intermediates 35 and more-facile proton-transfer reactions [29]. Meanwhile, protic solvent has the excellent microwave-absorbing ability to convert electromagnetic radiation into heat [30].…”

Recent Advances in Biocatalytic Promiscuity: Hydrolase‐Catalyzed Reactions for Nonconventional Transformations

“…Recently, the synthesis of benzo[ g ]chromenes has been described through a three‐component reaction, which involved the use of stoichiometric amounts of an aromatic aldehyde, malononitrile and 2‐hydroxy‐1,4‐naphthoquinone . After a reaction optimization study, ethanol, 55°C and Candida sp.…”

Promiscuous lipase catalyzed a new P–C bond formation: Green and efficient protocol for one‐pot synthesis of α‐aminophosphonates

“…Exploiting enzyme catalytic promiscuity provides new catalytic tools especially for multicomponent reactions (MCRs). These one‐pot reactions allow the creation of several bonds in one step with excellent chemical yields, reduction in reaction times and waste, toward the access to biologically important compounds [19]. Many reactions were successfully revisited, such as the Mannich reaction,[20] Morita‐Baylis‐Hillman reaction,[21] Knoevenagel reaction,[22] Henry reaction,[23] Michael addition,[24] and aldolization reaction [17e]…”