1: cyclopropyl-1,2-propadiene With lithium in tetrahydrofuran T=-10 - 0°C; 1 h; 2: dimethyl sulfate in tetrahydrofuran

1: cyclopropyl-1,2-propadiene With lithium in tetrahydrofuran T=10 - 20°C; 1 h; 2: dimethyl sulfate in tetrahydrofuran Further byproducts given;

magnesium iodide in diethyl ether Further byproducts given;