In 2018,Pandey, Khima; Rangan, Krishnan; Kumar, Anil published 《One-Pot Tandem Amidation, Knoevenagel Condensation, and Palladium-Catalyzed Wacker Type Oxidation/C-O Coupling: Synthesis of Chromeno-Annulated Imidazopyridines》.Journal of Organic Chemistry published the findings.Synthetic Route of C6H4BrNO The information in the text is summarized as follows:
N-(2-ethoxy-2-oxoethyl)-2-aminopyridinium bromides underwent one-pot tandem intramol. amidation, Knoevenagel condensation, Wacker-type oxidation, and intramol. C-O coupling reactions with bromoaryl aldehydes and β-bromo-α,β-unsaturated aldehydes in the presence of Pd(F3CCO2)2 and mediated by Cu(OAc)2, O2, and K3PO4 in aqueous DMF to yield chromenoimidazopyridinones such as I and pyranoimidazopyridinones in 28-77% yields. The mechanism of the reaction was studied; a bromobenzylideneimidazopyridinone intermediate was isolated and found to lead to I under the reaction conditions, and potential intermediates were observed by mass spectrometry. The experimental part of the paper was very detailed, including the reaction process of 2-Bromonicotinaldehyde(cas: 128071-75-0Synthetic Route of C6H4BrNO)
2-Bromonicotinaldehyde(cas: 128071-75-0) belongs to pyridine. Pyridines are often used as catalysts or reagents; particular notice has been paid recently to how pyridine coordinates to metal centers enabling a wide range of valuable reactions. Synthetic Route of C6H4BrNO