4471-22-1Relevant articles and documents
Remarkable Structural Diversity between Zr/Hf and Rare-Earth MOFs via Ligand Functionalization and the Discovery of Unique (4, 8)-c and (4, 12)-connected Frameworks
Angeli, Giasemi K.,Batzavali, Danai,Mavronasou, Katerina,Tsangarakis, Constantinos,Stuerzer, Tobias,Ott, Holger,Trikalitis, Pantelis N.
supporting information, p. 15986 - 15994 (2020/10/18)
Ligand modification in MOFs provides great opportunities not only for the development of functional materials with new or enhanced properties but also for the discovery of novel structures. We report here that a sulfone-functionalized tetrahedral carboxylate-based ligand is capable of directing the formation of new and fascinating MOFs when combined with Zr4+/Hf4+ and rare-earth metal cations (RE) with improved gas-sorption properties. In particular, the resulting M-flu-SO2 (M: Zr, Hf) materials display a new type of the augmented flu-a net, which is different as compared to the flu-a framework formed by the nonfunctionalized tetrahedral ligand. In terms of properties, a remarkable increase in the CO2 uptake is observed that reaches 76.6% and 61.6% at 273 and 298 K and 1 bar, respectively. When combined with REs, the sulfone-modified linker affords novel MOFs, RE-hpt-MOF-1 (RE: Y3+, Ho3+, Er3+), which displays a fascinating (4, 12)-coordinated hpt net, based on nonanuclear [RE9(μ3-?)2(μ3-??-)12(-COO)12] clusters that serve as hexagonal prismatic building blocks. In the absence of the sulfone groups, we discovered that the tetrahedral linker directs the formation of new RE-MOFs, RE-ken-MOF-1 (RE: Y3+, Ho3+, Er3+, Yb3+), that display an unprecedented (4, 8)-coordinated ken net based on nonanuclear RE9-clusters, to serve as bicapped trigonal prismatic building units. Successful activation of the representative member Y-ken-MOF-1 reveals a high BET surface area and total pore volume reaching 2621 m2 g-1 and 0.95 cm3 g-1, respectively. These values are the highest among all RE MOFs based on nonanuclear clusters and some of the highest in the entire RE family of MOFs. The present work uncovers a unique structural diversity existing between Zr/Hf and RE-based MOFs that demonstrates the crucial role of linker design. In addition, the discovery of the new RE-hpt-MOF-1 and RE-ken-MOF-1 families of MOFs highlights the great opportunities existing in RE-MOFs in terms of structural diversity that could lead to novel materials with new properties.
Zinc Chloride Mediated Nucleophilic Substitution: Amination and Thioetherification of Alcohols at Room Temperature
Gupta, Shruti,Khurana, Jitender M.,Singh, Ashima
, (2020/03/30)
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Design, synthesis and identification of a new class of triarylmethyl amine compounds as inhibitors of apolipoprotein e production
Singh, Mandeep,Schott, Jason T.,Leon, Martin A.,Granata, Robert T.,Dhah, Harkiran K.,Welles, Jason A.,Boyce, Michelle A.,Oseni-Olalemi, Hafeez S.,Mordaunt, Charles E.,Vargas, Anthony J.,Patel, Nilay V.,Maitra, Santanu
, p. 6252 - 6255 (2012/10/29)
We have identified a new class of triarylmethyl amine compounds that can inhibit apolipoprotein E (apoE) production. ApoE is a cholesterol- and lipid-carrier protein implicated in aging, atherosclerosis, Alzheimer's Disease (AD), and other neurological and lipid-related disorders. Attenuation of apoE production is generally considered to be of therapeutic value. A majority of the apoE in the brain is produced by astrocytes. Here, we describe the design, synthesis, and biological screening of a small library of compounds that led to the identification of four triarylmethyl amines as potent inhibitors of apoE production in CCF-STTG1 astrocytoma cells.