Helical Disubstituted Polyacetylenes: Synthesis and Chiroptical Properties of Poly(phenylpropiolate)s
作者:Jacky W. Y. Lam、Yuping Dong、Kevin K. L. Cheuk、Ben Zhong Tang
DOI:10.1021/ma0349433
日期:2003.10.1
cholesteryl (4)], are prepared by esterifications of phenylpropiolic acids with borneol, menthol, and cholesterol. Polymerizations of 1−4 are effected by WCl6−Ph4Sn, giving poly(phenylpropiolate)s P1−P4 with high molecular weights in moderate yields. The structures and properties of the polymers are characterized and evaluated by IR, UV, NMR, CD, TGA, and SEM analyses. All the polymers are stable: neither
由于涉及合成困难,很少制备具有螺旋手性的二取代聚乙炔,我们这里报道了一种用于合成这种聚合物的简便聚合体系。两组手性乙炔,即C 6 H 5 C⋮CCO 2 R * R * = [(1 S)-内]]-(-)-冰片基(1),(1 R,2 S,5 R) -(-)-薄荷基(5),胆固醇基(6)}和C 6 H 5 C⋮CCO 2 C 6 H 4 CO 2 R * [R * =降冰片基(2),薄荷基(3),胆固醇基(4)]是通过苯丙酸与冰片,薄荷醇和胆固醇的酯化反应制得的。的聚合1 - 4由WCL实现6 -Ph 4的Sn,得到的聚(苯基丙)性s P 1 -P 4具有高分子量,产率中等。通过IR,UV,NMR,CD,TGA和SEM分析来表征和评估聚合物的结构和性质。所有聚合物都是稳定的:在将聚合物储存在架子上约3年后,分子量均未降低,光谱也未发现变化,并且将聚合物加热至300°C时,未发现重量损失。尽管
First Fullerene[60]-Containing Thermotropic Liquid Crystal. Preliminary Communication
作者:Thierry Chuard、Robert Deschenaux
DOI:10.1002/hlca.19960790316
日期:1996.5.8
The synthesis and liquid-crystalline and thermal properties of a fullerene[60] functionalized by a framework containing two cholesterol derivatives through a methanofullerene structure are reported. The targeted fullerene derivative showed high thermal stability.
An amphiphilic trinuclear cobalt cluster-containing molecular unit: synthesis, characterization and Langmuir–Blodgett films
作者:Robert Deschenaux、Claudio Masoni、Helen Stoeckli-Evans、Sebastien Voucher、Jürgen Ketterer、Rolf Steiger、Albrecht L. Weisenhorn
DOI:10.1039/dt9940001051
日期:——
An amphiphilic polynuclear transition-metal cluster has been prepared and its capability for forming layers at the air–water interface and Langmuir–Blodgett films on different substrates investigated. The compound was obtained by linking a Co3(CO)9 cluster to a hydrophobic cholesterol framework. A polar head was introduced by substituting one CO ligand by an isocyanide derivative bearing a hydrophilic
已经制备了两亲性多核过渡金属簇,并研究了其在空气-水界面和在不同基材上的Langmuir-Blodgett膜上形成层的能力。该化合物是通过将Co 3(CO)9簇连接到疏水性胆固醇骨架上而获得的。通过用带有亲水性官能团的异氰酸酯衍生物取代一个CO配体来引入极性头。表面压力和表面电势与面积等温线和布鲁斯特角显微镜表明形成了稳定的Langmuir膜。在疏水化的固体(云母,玻璃,石英和硅片)上进行了多达三十六次转移。转移膜的结构表征(紫外和红外光谱,原子力显微镜,电子邮件角度X射线散射)表明形成了稳定的,高度组织化的晶体。结果代表了从多核过渡金属化合物和有机金属表面发展超分子组装的新策略。通过X射线晶体学已经确定了[Co 3(CO)8(CCO 2 Me)(CNC 6 H 4 CN)]的结构。
A Mixed Fullerene–Ferrocene Thermotropic Liquid Crystal: Synthesis, Liquid-Crystalline Properties, Supramolecular Organization and Photoinduced Electron Transfer
作者:Michaël Even、Benoit Heinrich、Daniel Guillon、Dirk M. Guldi、Maurizio Prato、Robert Deschenaux
of a ferrocene-containing liquid-crystalline malonate derivative to C60 led to the mixed fullerene-ferrocene material 1 which gave rise to a smectic A phase. Cholesterol was used as liquid-crystalline promoter. X-ray diffraction experiments and volumetric measurements indicated that 1 is organized in double layered structures. The corresponding supramolecularorganization within the mesomorphic lamellar
Rapid Access to Free Phenols by Photocatalytic Acceptorless Dehydrogenation of Cyclohexanones at Room Temperature
作者:Lin Min、Jiani Lin、Wei Shu
DOI:10.1002/cjoc.202300363
日期:2023.11
conditions remain challenging. Herein, a photocatalytic acceptorless hydrogen-evolution aromatization of cyclohexanones or cyclohexenones at roomtemperature has been developed. The reaction features the visible-light and cobalt co-catalyzed sequential dehydrogenation of in-situ formed enol silyl ethers, which are regarded as a challenging process. This operationally simple method enables the synthesis