Chemoselective Transformations of Amides: An Approach to Quinolones from β-Amido Ynones.

An efficient and chemoselective transformation of β-amido ynones to 3-acyl-substituted quinolones 2 and 3-H-quinolones 4 has been developed. In this reaction, β-cyclic amido ynones can be selectively transformed into quinolones 2 in anhydrous EG via a selective C═O bond cleavage, 1,5-O migration, and C═C bond recombination process. The practical approach of this reaction renders it a viable alternative for the construction of various quinolones.