Benzylidene-functionalized ruthenium-based olefin metathesis catalysts for ring-opening metathesis polymerization in organic and aqueous media

New catalysts (PCy3)(2)Cl2Ru=CH(p-C6H4)CH2P(CH3)(3)Cl-+(-) (5) and (PCy3)(2)Cl2Ru=CH(p-C6H4)CH2-N(CH3)(2) (6) as well as the literature compound (PCy3)(2)Cl2Ru=CH(pC(6)H(4))N(CH3)(2) (7) have been synthesized via alkylidene exchange from Grubbs' catalyst in a one-step reaction. The catalysts promoted ROMP of the cationic exo-7-oxanorbornene derivative 11 under homogeneous conditions in various protic media including aqueous/alcoholic 1:1 mixtures, and in many cases, particularly for catalysts 5 and 6, the polymerizations proceeded in a controlled manner.