Synthesis of 5-methylfuro[3,2- c]quinolin-4(5 H)-one via palladium-catalysed cyclisation of N-(2-iodophenyl)- N-methyl-3-furamide

• Published in: Tetrahedron letters Vol. 47; no. 42; pp. 7493 - 7495
• Main Authors: Lindahl, Karl-Fredrik, Carroll, Anthony, Quinn, Ronald J., Ripper, Justin A.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 16-10-2006
• Subjects: Furoquinolinones; Palladium catalyst; Palladium oxide; Palladium catalyst; Palladium oxide; Furoquinolinones
• ISSN: 0040-4039; 1873-3581
• DOI: 10.1016/j.tetlet.2006.08.032

A new method for the synthesis of 5-methylfuro[3,2-
c]quinolin-4(5
H)-one has been developed and the palladium-catalysed cyclisation step has been shown to give the best yields when palladium oxide was used as the catalyst.
A new synthesis of the furo[3,2-
c]quinolin-4(5
H)-one heterocycle has been developed using a palladium-catalysed cyclisation of
N-(2-iodophenyl)-
N-methyl-3-furamide. By varying the catalyst, base and solvent, the yield of the cyclisation was optimised. It was found that the use of palladium oxide with potassium acetate in
N,
N-dimethylacetamide (DMA) with a small amount of tetrabutylammonium chloride gave the highest yield of 5-methylfuro[3,2-
c]quinolin-4(5
H)-one (
9).