Under mild conditions and hydrogen atmosphere, the low-valence Chin catalytic system composed of Cp2TiCl2 and i-rPMgBr not only has good hydrogenation activity for 1,5-cyclooctadiene, but also isomerizes olefins. The catalyst can either linearly isomerize 1,5-hexadiene or cyclic isomerization. In this paper, the hydrogenation reaction of 6,6-diphenylfulvene, a low-valent Chinchin catalyst composed of ChemicalbookCp2TiCl2 and i-rPMg-Br, under mild conditions and hydrogen atmosphere, was studied, which can partially hydrogenate the polyolefin and isomerize the partial hydrogenation products. The final product retains the double bond and is not easily hydrogenated to substituted cyclopentane, and no linear isomerization occurs in the reaction