Designing a catalytic synthesis of 4-methylcoumarin from ortho-iodophenyl 3-butenoate: Ring closure and isomerization control
作者:Marta Catellani、Gian Paolo Chiusoli、Giovanna Marzolini、Emanuela Rossi
DOI:10.1016/s0022-328x(96)06489-3
日期:1996.11
The palladium-catalyzed ringclosure of ortho0iodophenyl 3-butenoate to 4-methylcoumarin is in competition with the isomerization to the 2-butenoic ester; the latter reaction has been controlled by the appropriate use of ligands, solvents and neutralizing agents to the point that quantitative yields of the cyclic compound have been attained.