132356-66-2Relevant articles and documents
In(OTf)3-catalysed easy access to dihydropyranocoumarin and dihydropyranochromone derivatives
Boufroua, Naouel,Dunach, Elisabet,Fontaine-Vive, Fabien,Poulain-Martini, Sophie,Boufroua, Naouel,Achouche-Bouzroura, Samia
supporting information, p. 6042 - 6052 (2020/04/27)
We developed an easy, In(OTf)3-catalysed, regioselective and generalizable method, for allylation/cyclization of β-ketolactone-type heterocyclic compounds. This reaction is proposed to proceed one-pot, through a Friedel-Crafts C-allylation followed by cyclization. This process represents a green synthetic method, as AcOH is the only isolated byproduct. We propose here, a protocol applicable for the construction of biologically active dihydropyranocoumarin and dihydropyranochromone derivatives.
The Chemistry of Coumarin Derivatives Synthesis of 3-Alkyl-4-hydroxycoumarins by Reductive Fragmentation of 3,3'-Alkylidene-4,4'-dihydroxybis
Appendino, Giovanni,Cravotto, Giancarlo,Tagliapietra, Silvia,Ferraro, Stefano,Nano, Gian Mario,Palmisano, Giovanni
, p. 1451 - 1458 (2007/10/02)
Treatment of 3,3'-alkylidene-4,4'-dihydroxybis 1 with NaBH3CN in refluxing MeOH affords 3-alkyl-4-hydroxycoumarins 2 and 4-hydroxycoumarin (3; Scheme 1).The reaction may take place via hydride trapping of alkylidenechromandiones C formed from 1 in a retro-Michael reaction.Such a retro-Michael reaction of 1 might be biologically relevant.The presence of C during the reductive fragmentation 1 --> 2 is suggested by Diels-Alder and nucleophilic trapping of the alkylidenechromandiones C as well as from cross-over experiments with coumarins other than 3 (see Scheme 2).The reductive fragmentation of 1 allows the chemo- and regioselective synthesis of a variety of 3-alkyl-4-hydroxycoumarins 2 (see Table).
