Synthesis of water-soluble, aliphatic phosphines and their application to well-defined ruthenium olefin metathesis catalysts

Water-soluble aliphatic phosphines Cy(2)P(CH2)(2)N(CH3)(3)Cl-+(-) (14), Cy(2)P[4-(N,N-dimethyl-piperidinium)]Cl-+(-) (15), Cy(2)P(CH2)(2)SO3-Na+ (16), and CyP[(CH2)(2)N(CH3)(3)Cl-+(-)](2) (17) (Cy = cyclohexyl) were prepared from air-stable, borane-protected precursors. Spectroscopic investigations of corresponding Pd(PR(3))(2)Cl-2 complexes were used to estimate the steric parameters of these new phosphines. Spectroscopic investigation of Ni(CO)(3)PR(3) complexes of the new phosphines indicated that phosphines bearing quaternary amine functionalities were less electron donating than tricyclohexylphosphine, while the presence of a sulfonate group increased phosphine electron donation. Cationic phosphines 14 and 15 were used to synthesize water-soluble ruthenium carbene complexes of the type (Cy(2)PR)(2)Cl2Ru=CHPh. These complexes initiate the ring-opening metathesis polymerization (ROMP) of functionalized 7-oxanorbornenes in water, methanol, and aqueous emulsions.