One-Pot Chemoselective Bis(Suzuki-Miyaura Cross-Coupling): Efficient Access to 3,9-Bis[(hetero)aryl]-4H-pyrido[1,2-a]pyrimidin-4-one Derivatives Under Microwave Irradiation

A one-pot chemoselective bis(SuzukiMiyaura cross-coupling) reaction under microwave irradiation is reported for the 4H-pyrido[1,2-a]pyrimidin-4-one series. First, we ascertained an initial coupling reaction that was selectively carried out at the C-3 position of (7,9-dichloro-3-iodo-4-oxo-4H-pyrido[1,2-a]pyrimidin-2-yl)methyl acetate (4). Next, we developed an extremely efficient one-pot chemoselective bis(SuzukiMiyaura cross-coupling) reaction, allowing us to substitute successively at the 3- and then at the 9-position of compound 4 with various boronic acids.