2,5-Dimethoxy-2,5-dihydrofuran and vinyl ethers in the synthesis of functionalised 2-alkylfurans

2,5-Dimethoxy-2,5-dihydrofuran reacts, in the presence of a catalytic amount of MgBr2·Et2O with the appropriate vinyl ether, to give functionalised 2-alkylfurans with good yield and mild reaction conditions, this represents a useful synthetic approach to 2-(2-furo)tetrahydro -furanic or -pyranic moieties. The reaction fails on using deactivated or α-substituted vinyl ethers.