1. Organic Salts and Merrifield Resin Supported [PM12O40]3- (M = Mo or W) as Catalysts for Adipic Acid Synthesis
Jana Pisk, Dominique Agustin, Rinaldo Poli Molecules. 2019 Feb 21;24(4):783. doi: 10.3390/molecules24040783.
Adipic acid (AA) was obtained by catalyzed oxidation of cyclohexene, epoxycyclohexane, or cyclohexanediol under organic solvent-free conditions using aqueous hydrogen peroxide (30%) as an oxidizing agent and molybdenum- or tungsten-based Keggin polyoxometalates (POMs) surrounded by organic cations or ionically supported on functionalized Merrifield resins. Operating under these environmentally friendly, greener conditions and with low catalyst loading (0.025% for the molecular salts and 0.001⁻0.007% for the supported POMs), AA could be produced in interesting yields.
2. Merrifield Resin-C6H4CH2N3P(MeNCH2CH2)3N: an efficient reusable catalyst for room-temperature 1,4-addition reactions and a more convenient synthesis of its precursor P(MeNCH2CH2)3N
Chinta Reddy Venkat Reddy, John G Verkade J Org Chem. 2007 Apr 13;72(8):3093-6. doi: 10.1021/jo062505z. Epub 2007 Mar 17.
1,4-additions to a variety of Michael acceptors with a wide variety of donors were efficiently catalyzed at room temperature by the title reusable Merrifield resin-supported catalyst. Advantages of this catalyst include a simple workup (filtration of the reaction mixture) and good to excellent product yields. We also report a substantially simplified synthesis of the commercially available strong nonionic base 1, a precursor to the title polymer-bound catalyst.
3. Grubbs Catalysts Immobilized on Merrifield Resin for Metathesis of Leaf Alcohols by using a Convenient Recycling Approach
Liang Xia, Tao Peng, Gang Wang, Xiaoxue Wen, Shouguo Zhang, Lin Wang ChemistryOpen. 2019 Jan 15;8(1):45-48. doi: 10.1002/open.201800188. eCollection 2019 Jan.
Three new types of heterogeneous catalysts were prepared using a facile approach by the immobilization of Grubbs catalysts on PEGylated Merrifield resin. One of the immobilized catalysts was more efficient than the free catalyst for the metathesis of leaf alcohols in conversion and selectivity and was reused repeatedly (up to 5 cycles) with only a slight loss of activity (10.5 %). The long-chain PEGylated linker provided an appropriate distance between the resin and the catalytic center so that the ruthenium catalysts acted as the free catalyst.
