The interaction of dihydrofurylsilanes with dichlorocarbene under phase-transfer conditions

Dichlorocarbene generated in a two-phase catalytic system reacts with 3-trimethylsilyl-2,5-dihydrofuran to give both possible products of mono-insertion into the CH bond in positions 2 and 5 of the ring, together with a CC bond adduct. Reaction of 2-trimethylsilyl-4,5-dihydrofuran with dichlorocarbene leads to 2,3-dichloro-2-trimethylsilyl-5,6-dihydro-2H-pyran, which is formed via isomerization of the primary bicyclic adduct.