A Convenient Approach to the Synthesis of Dialkyl 5‐Oxo‐1,2‐dihydro‐5<i>H</i>‐chromeno [4,3‐<i>b</i>]pyridine‐2,3‐dicarboxylates
                                
                                    
                                        作者:Toma N. Glasnov、Ivo C. Ivanov                                    
                                    
                                        DOI:10.1080/00397910801929465
                                    
                                    
                                        日期:2008.4.1
                                    
                                    Coumarin and its analogs are considered privileged scaffolds in the current synthetic and pharmacological research. The chemical behavior of enaminocarbaldehydes of the coumarin moiety under intramolecular Wittig reaction conditions in the presence of triphenylphosphine and dimethyl or diethyl acetylenedicarboxylates has been studied, resulting in the isolation of a series of dimethyl and diethyl 5-oxo-1,2-dihydro-5H-chromeno[4,3-b]pyridine-2,3-dicarboxylates in good to high yields.