Living ring-opening metathesis polymerization of cyclopropenes

The living ring-opening metathesis polymerization (ROMP) of the substituted cyclopropanes using high oxidation state molybdenum initiators, was illustrated. ROMP of 3-methyl-3-phenylcyclopropene (A) in tetrahydrofuran at room temperature using the initiators 1, 2, or 3, produced ROMP polymers in 94-97% yield. After one hour, the reactions were quenched through addition of excess benzaldehyde which reacted in a Wittig-like manner to yield benzylidene-capped polymers. The differential scanning calorimetry (DSC) studies on A 100C 100A 100 have shown homogeneous microphases with a broad transition centered at 0 °C.