M. Catellani et al., A NEW PALLADIUM-CATALYZED SYNTHESIS OF 3,4-DISUBSTITUTED COUMARINS FROM 3-ALKENOATES OF ORTHO-IODOPHENOL, PHENYLACETYLENE AND CARBON-MONOXIDE, Tetrahedron letters, 35(32), 1994, pp. 5923-5926
Palladium(0) has been found to catalyse the reaction of an aromatic ca
rbon-iodide bond with carbon monoxide, the triple bond of alkynes and
the allylic carbon of an ortho alkenoic chain to form a 3,4-disubstitu
ted coumarin ring in satisfactory yield under mild conditions.