Mechanical forces have previously been used to drive reactions along pathways that violate the orbital symmetry effects captured in the Woodward鈥揌offmann rules. Here, we show that a polymer 鈥渓ever arm effect鈥?can provide a mechanical advantage in accelerating the symmetry forbidden disrotatory ring opening of benzocyclobutene (BCB). Addition of an 伪-E-alkene to the BCB mechanophore drops the force required to induce reactions on the 鈭?.1 s time scale of single-molecule force spectroscopy experiments from 1370 to 920 pN.