作者:Demetrius A. Vazquez-Molina、Giovanna M. Pope、Andrew A. Ezazi、Jose L. Mendoza-Cortes、James K. Harper、Fernando J. Uribe-Romo
DOI:10.1039/c8cc04292f
日期:——
family of covalentorganicframeworks that have been functionalized with oligo-(ethylene oxide) chains of varying lengths. Because of the open structure of the COFs, the side chains do not interfere with their crystallization obtaining materials with predictable crystal structure. The difference in length of the side-chains allowed for the determination of amphidynamic behaviour with the use of 13C solid-state
The influence of crystal packing on the solid state fluorescence behavior of alkyloxy substituted phenyleneethynylenes
作者:Reji Thomas、Shinto Varghese、G. U. Kulkarni
DOI:10.1039/b902937k
日期:——
The study reports the solid state photophysical properties of a series of alkyloxy-substituted oligo(phenyleneethynylene)s, methoxy to hexyloxy, supported by a detailed analysis of molecular packing obtained from single crystal X-ray diffraction data. While the emission peaks are highly red shifted (by as much as 114 nm) in the solid state, all molecules exhibit similar absorption and emission in dilute solutions. The red shift is maximum in ethoxy and minimum in methoxy, while other crystalline films exhibit intermediate values. In the crystal structures, the spacing between the molecular pairs forming the J-aggregates is varied between 3.48 to 4.65 Å, with no systematic dependence on the chain length. The red shifted emission maximum is found to vary linearly with the spacing between the interacting molecules in the J-aggregate. Thus, the emission in the solid state is determined by the extent of dipolar coupling between the molecules, the alkyl chain length influencing the properties only indirectly.
[EN] MECHANICALLY SHAPED 2-DIMENSIONAL COVALENT ORGANIC FRAMEWORKS<br/>[FR] STRUCTURES ORGANIQUES COVALENTES BIDIMENSIONNELLES À FORME MÉCANIQUE
申请人:UNIV CENTRAL FLORIDA RES FOUND INC
公开号:WO2018013682A1
公开(公告)日:2018-01-18
Covalent organic frameworks (COFs) usually crystallize as insoluble powders and their processing for suitable devices has been thought to be limited. Here, it is demonstrated that COFs can be mechanically pressed into shaped objects having anisotropic ordering with preferred orientation between the hk0 and 00/ crystallographic planes. Pellets prepared from bulk COF powders impregnated with LiC1O4 displayed room temperature conductivity up to 0.26 mS cm-1 and stability up to 10.0 V (vs. Li+/Li0). This outcome portends use of COFs as solid-state electrolytes in batteries.
共价有机框架(COFs)通常结晶为不溶性粉末,人们认为它们的加工适用于设备的可能性受到限制。在这里,证明了COFs可以被机械压制成具有各向异性排序的成型物体,其在hk0和00/晶体学平面之间具有优选取向。由浸渍LiC1O4的大块COF粉末制备的颗粒在室温下显示出高达0.26 mS cm-1的电导率,并且在10.0 V(相对于Li+/Li0)的稳定性。这一结果预示着COFs可用作电池中的固态电解质。
The synthesis and conformation of oxygenated trianglimine macrocycles
作者:Nikolai Kuhnert、Ana Lopez-Periago、Giulia M. Rossignolo
DOI:10.1039/b414747m
日期:——
The synthesis of series of D2h and C2v symmetric oxygenated aromatic dicarboxaldehydes, using dilithiation methodology, is described along with their reactivity in the [3 + 3] cyclocondensation reaction with (1R,2R)-diaminocyclohexane to give oxygenated trianglimine macrocycles. Macrocycles derived from C2v symmetric dialdehydes give macrocycles with a stereogenic aromatic plane with complete diastereocontrol, as a mixture of rotamers.