79615-75-1Relevant academic research and scientific papers
Phosphazene Base tBu-P4 Catalyzed Methoxy–Alkoxy Exchange Reaction on (Hetero)Arenes
Shigeno, Masanori,Hayashi, Kazutoshi,Nozawa-Kumada, Kanako,Kondo, Yoshinori
supporting information, p. 6077 - 6081 (2019/03/26)
The organic superbase tBu-P4 catalyzes methoxy-alkoxy exchange reactions on (hetero)arenes with alcohols. The catalytic reaction proceeded efficiently with electron-deficient methoxy(hetero)arenes as well as with a variety of alcohols, including 3-amino-1-propanol, β-citronellol, menthol, and cholesterol. An intramolecular version of this reaction furnished six- and seven-membered ring compounds.
Metal-organic layers as multifunctional two-dimensional nanomaterials for enhanced photoredox catalysis
Lan, Guangxu,Quan, Yangjian,Wang, Maolin,Nash, Geoffrey T.,You, Eric,Song, Yang,Veroneau, Samuel S.,Jiang, Xiaomin,Lin, Wenbin
supporting information, p. 15767 - 15772 (2019/10/11)
Metal-organic layers (MOLs) have recently emerged as a novel class of molecular two-dimensional (2D) materials with significant potential for catalytic applications. Herein we report the design of a new multifunctional MOL, Hf12-Ir-Ni, by laterally linking Hf12 secondary building units (SBUs) with photosensitizing Ir(DBB)[dF(CF3)ppy]2+ [DBB-Ir-F, DBB = 4,4′-di(4-benzoato)-2,2′-bipyridine; dF(CF3)ppy = 2-(2,4-difluorophenyl)-5-(trifluoromethyl)pyridine] bridging ligands and vertically terminating the SBUs with catalytic Ni(MBA)Cl2 [MBA = 2-(4′-methyl-[2,2′-bipyridin]-4-yl)acetate] capping agents. Hf12-Ir-Ni was synthesized in a bottom-up approach and characterized by TEM, AFM, PXRD, TGA, NMR, ICP-MS, UV-vis, and luminescence spectroscopy. The proximity between photosensitizing Ir centers and catalytic Ni centers (～0.85 nm) in Hf12-Ir-Ni facilitates single electron transfer, leading to a 15-fold increase in photoredox reactivity. Hf12-Ir-Ni was highly effective in catalytic C-S, C-O, and C-C cross-coupling reactions with broad substrate scopes and turnover numbers of ～4500, ～1900, and ～450, respectively.
Switching on elusive organometallic mechanisms with photoredox catalysis
Terrett, Jack A.,Cuthbertson, James D.,Shurtleff, Valerie W.,MacMillan, David W.C.
, p. 330 - 334 (2015/09/01)
Transition-metal-catalysed cross-coupling reactions have become one of the most used carbon-carbon and carbon-heteroatom bond-forming reactions in chemical synthesis. Recently, nickel catalysis has been shown to participate in a wide variety of C-C bond-forming reactions, most notably Negishi, Suzuki-Miyaura, Stille, Kumada and Hiyama couplings. Despite the tremendous advances in C-C fragment couplings, the ability to forge C-O bonds in a general fashion via nickel catalysis has been largely unsuccessful. The challenge for nickel-mediated alcohol couplings has been the mechanistic requirement for the critical C-O bond-forming step (formally known as the reductive elimination step) to occur via a Ni(iii) alkoxide intermediate. Here we demonstrate that visible-light-excited photoredox catalysts can modulate the preferred oxidation states of nickel alkoxides in an operative catalytic cycle, thereby providing transient access to Ni(iii) species that readily participate in reductive elimination. Using this synergistic merger of photoredox and nickel catalysis, we have developed a highly efficient and general carbon-oxygen coupling reaction using abundant alcohols and aryl bromides. More notably, we have developed a general strategy to 'switch on' important yet elusive organometallic mechanisms via oxidation state modulations using only weak light and single-electron-transfer catalysts.
HTS followed by NMR based counterscreening. Discovery and optimization of pyrimidones as reversible and competitive inhibitors of xanthine oxidase
Even?s, Johan,Edfeldt, Fredrik,Lepist?, Matti,Svitacheva, Naila,Synnergren, Anna,Lundquist, Britta,Gr?nse, Mia,R?nnholm, Anna,Varga, Mikael,Wright, John,Wei, Min,Yue, Sherrie,Wang, Junfeng,Li, Chong,Li, Xuan,Chen, Gang,Liao, Yong,Lv, Gang,Tj?rnebo, Ann,Narjes, Frank
supporting information, p. 1315 - 1321 (2014/03/21)
The identification of novel, non-purine based inhibitors of xanthine oxidase is described. After a high-throughput screening campaign, an NMR based counterscreen was used to distinguish actives, which interact with XO in a reversible manner, from assay artefacts. This approach identified pyrimidone 1 as a reversible and competitive inhibitor with good lead-like properties. A hit to lead campaign gave compound 41, a nanomolar inhibitor of hXO with efficacy in the hyperuricemic rat model after oral dosing.
