1070987-49-3Relevant academic research and scientific papers
Povarov reactions involving 3-aminocoumarins: Synthesis of 1,2,3,4-tetrahydropyrido[2,3-c]coumarins and pyrido[2,3-c]coumarins
Kudale, Amit A.,Kendall, Jamie,Miller, David O.,Collins, Julie L.,Bodwell, Graham J.
supporting information; experimental part, p. 8437 - 8447 (2009/04/11)
(Chemical Equation Presented) Condensation of 3-aminocoumarin (5) with 4-nitrobenzaldehyde (8) afforded a 2-azadiene (9), which reacted with various electron-rich alkenes (10 examples) in the presence of Yb(OTf)3 to afford 1,2,3,4-tetrahydropyrido[2,3-c]coumarins. Yields were generally good, but the diastereomeric ratios were highly variable. The products arose through a formal [4 + 2] cycloaddition (inverse electron demand Diels-Alder reaction) followed by tautomerization. As such, these are examples of the Povarov reaction. A range of 1,2,3,4-tetrahydropyrido[2,3-c]coumarins was then synthesized using a three-component version of this reaction, which involves in situ formation of the 2-azadiene component. Some of these products were converted into the corresponding pyrido[2,3-c]coumarins upon treatment with various oxidants, the most effective of which proved to be nitrous gases.
