Two metathesis catalysts, RuCl₂(PCy₃)(NHC)(CHPh) (1) [NHC=1-(2,4,5-trimethylphenyl)-3-(6-hydroxyhexyl)-imidazol-2-ylidene] and Mo(N-2,6-i-Pr₂-C₆H₃)(CHCMe₂Ph)(BIPHEN) (2) [BIPHEN=(R)-3,3′-di-t-butyl-5,5′,6,6′-tetramethyl-2,2′-biphenolate) have been immobilized on polymeric, monolithic discs using a “grafting from” protocol. Monolithic discs were prepared via ring-opening metathesis polymerization (ROMP) from norborn-2-ene (NBE), tris(norborn-5-ene-2-ylmethyleneoxy)methylsilane [(NBE-CH₂O)₃-SiCH₃], 2-propanol, toluene and RuCl₂(PCy₃)₂(CHPh). Catalyst loadings of 0.55 and 0.7 wt %, respectively, were obtained. Monolithic disc-immobilized 1 was used in various metathesis-based reactions including ring-closing metathesis (RCM), ring-opening cross metathesis and enyne metathesis. Using 0.23–0.59 mol % of supported 1, turnover numbers (TONs) up to 330 were achieved. Monolithic disc-immobilized 2 was used in various enantioselective RCM and desymmetrization reactions. Using 9–13 mol % of supported catalyst, excellent yields up to 100% and high enantiomeric excess (ee≤88%) were observed. In both cases, metal leaching was low (≤3 and ≤2%, respectively). In addition, 1 catalyzed the cyclopolymerization of diethyl dipropargylmalonate (DEDPM) to yield poly(ene)s consisting of 5-membered rings, i.e., cyclopent-1-ene-1-vinylene units. The polymerization proceeded via non-stoichiometric initiation yielding polymers with unimodal molecular weight distribution. Using a catalyst to monomer ratio of 1 : 170, molecular weights of M_w=16,400 and M_n=11,700 g/mol, PDI=1.40 were obtained

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A permanently polymer-immobilised version of Schrock's molybdenum catalyst was realised via polymerisation of chiral 5,5'-bis(norborn-5-ene-2-ylmethyleneoxymethyl)-3,3'-di-tert-butyl-6,6'-dimethylbiphen-2,2'-diol followed by reaction with the catalyst precursor Mo(N-2,6-i-Pr2C6H3)(CHCMe2Ph)(OSO2CF3)2(CH3OCH2CH2OCH3); using this 5-, 6- and 7-membered heterocycles were synthesised via ring-closing metathesis (RCM) from (pro-)chiral substrates in high yields and ee with short reaction times; the catalyst shows low loss of molybdenum during RCM, and was easily separated and recycled.

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