Efficient palladium-catalyzed cross-coupling reactions of α-diazocarbonyl compounds and arylboronic acids or arylhalides have been developed. The reaction proceeds smoothly for a range of diazo compounds, boronic acids, and halides. The coupling reaction conditions tolerate various substituents on the aromatic rings of the substrates, such as chloro, fluoro, acyl, oxo, ester, and nitro groups. This