In Situ Hydrogenation of Terminal Halogen in Poly(methyl methacrylate) by Ruthenium-Catalyzed Living Radical Polymerization: Direct Transformation of “Polymerization Catalyst” into “Hydrogenation Catalyst”

An in situ, selective, and quantitative hydrogenation of the terminal chlorine (alpha-haloester) in living PMMA-Cl into PMMA-H was achieved via direct transformation of a "polymerization catalyst" into a "hydrogenation catalyst" in the Ru(II)-catalyzed living radical polymerization, where the polymerization mixture of MMA was directly treated in situ with K2CO3 as a base and 2-propanol as a hydrogen donor. The reaction terminated the polymerization and, more importantly, the terminal chlorine was quantitatively hydrogenated, as confirmed by SEC, 1H NMR, and MALDI-TOF MS.