1234-27-1Relevant articles and documents
Urea-based flexible dicarboxylate linkers for three-dimensional metal-organic frameworks
Glomb, Sebastian,Makhloufi, Gamall,Gruber, Irina,Janiak, Christoph
, p. 35 - 46 (2018)
The metal-organic frameworks (MOFs) 3D-[Mn2(L1)2(DMF)]·2DMF (1), 3D-[Cd2(L2)2(DMF)3] (3), [Zn2(L2)2(DMF)3] (4) and 3D-[Mn2(L2)2(DMF)3] (5) are the first examples of three-dimensional metal-organic networks constructed from a single ditopic dicarboxylate linker (i.e., without bridging co-ligands) with an urea group in the linker axis (L12? = 4,4′-(carbonylbis(azanediyl))dibenzoate; L22? = 4,4′-(carbonylbis(azanediyl))bis(3-methylbenzoate), DMF = dimethylformamide). From Cd2+and L12? a 1D coordination polymer 1D-[Cd(L1)(DMF)3] (2) is formed. The urea group is engaged in hydrogen bonding with the C(4)[R12(6)] motif to an oxygen atom of a DMF solvent (in 1) or a metal-coordinated carboxylate group (in 3–5). Network 1 has infinite channels with parallelepiped cross sections and 30% solvent-filled volume. The 3 D frameworks 3–5 are of diamond (6,6), dia topology with a single framework having large voids with 17.6 ? and 19.7 ? nodal separation. Thus, four symmetry-related nets interpenetrate, organized via H-bonds in the C(4)[R12(6)] motif, still leaving about 50% solvent-filled void volume in the fourfold interpenetrated structure.
Concise and Additive-Free Click Reactions between Amines and CF3SO3CF3
Song, Hai-Xia,Han, Zhou-Zhou,Zhang, Cheng-Pan
supporting information, p. 10907 - 10912 (2019/08/02)
Trifluoromethyl trifluoromethanesulfonate has proved to be an excellent reservoir of difluorophosgene and a promising click ligation for amines in the preparation of urea derivatives, heterocycles, and carbamoyl fluorides under metal- and additive-free conditions. The reactions are rapid, efficient, selective, and versatile, and can be performed in benign solvents, giving products in excellent yields with minimal efforts for purification. The characteristics of the reactions meet the requirements of a click reaction. The use of trifluoromethyl trifluoromethanesulfonate as a click reagent is advantageous over other “CO” sources (e.g., TsOCF3, PhCO2CF3, CsOCF3, AgOCF3, and triphosgene) because this reagent is readily accessible; easy to scale up; and highly reactive, even under metal- and additive-free conditions. It is anticipated that CF3SO3CF3 will be increasingly as important as SO2F2 as a click agent in future drug design and development.
Urea-containing metal-organic frameworks as heterogeneous organocatalysts
Tehrani, Alireza Azhdari,Abedi, Sedigheh,Morsali, Ali,Wang, Jun,Junk, Peter C.
, p. 20408 - 20415 (2015/10/19)
Two novel pillared metal-organic frameworks (MOFs) containing a urea-functional group are introduced. Herein, the urea functional group was incorporated into the MOF backbone by preparing a urea-ditopic ligand. These frameworks (TMU-18 and TMU-19) were fabricated using the synthesized urea-containing ligand, 4,4′-bipyridine (bipy) and 1,2-bis(4-pyridyl)ethane (bpe), and using zinc nitrate as the metal source. Subsequently, TMU-18 and TMU-19 were characterized by X-ray diffraction, IR spectroscopy, elemental analysis, scanning electron microscopy (SEM) and thermogravimetric analysis. Furthermore, their potential efficiency as organocatalysts was evaluated in the regioselective methanolysis of epoxides.