Sonogashira-Heteroannulative Route to Dihydroisobenzofurans

Significance

Reported is a synthesis of dihydroisobenzofurans via a Sonogashira-hetero­annulation strategy. 2-Bromoaryl and 3-pyridyl ­aldehydes, terminal alkynes and methanol are employed in this one-pot, microwave-assisted process under palladium and copper catalysis to afford dihydroisobenzofurans in good to excellent yields. The Sonogashira cross-coupling is followed by t-BuOK-generated methoxide annulations, which may also involve metal catalysis. The scope of substituents on the aromatic was not well investigated.