Furfural and itsderivatives underwent alkenylation with alkynes via α‐C−H activation in the presence of a palladium/carboxylicacid catalyst to give the corresponding single and double alkenylated products. The reactive aldehyde group remained intact during this reaction. This catalytic system allowed selective alkenylation of furan substrates having electron‐withdrawing substituents.
ADDITION OF 5-MEMBERED AROMATIC HETEROCYCLIC COMPOUNDS TO ACETYLENES CATALYZED BY TETRARHODIUM DODECACARBONYL: SYNTHESES OF VINYL SUBSTITUTED AROMATIC HETEROCYCLIC COMPOUNDS
作者:Pangbu Hong、Bo-Re Cho、Hiroshi Yamazaki
DOI:10.1246/cl.1980.507
日期:1980.5.5
In the presence of a catalytic amount of Rh4(CO)12 furan adds to diphenylacetylene (1a) to give 1-(2-furyl)-1,2-diphenylethylene in a 80% yield. Similarly, from 2-substituted furans are obtained the adducts (3e–3h), in which the furyls attach to the olefin at the 5-position of the rings, in good yields. Thiophene and N-methylpyrrole also react with 1a to afford the corresponding ethylenes.