Synthesis of 1H-isochromen-1-ylphosphonates via AgOTf-catalyzed reaction of 2-alkynylbenzaldehyde with diethyl phosphite

Tandem cyclization-addition reaction of 2-alkynylbenzaldehyde with diethyl phosphite catalyzed by AgOTf at room temperature was developed, which afforded the desired 1H-isochromen-1-ylphosphonates in moderate to good yields.