在这项研究中,我们发现官能团对邻碳硼烷基物质上芳香族单元的电子效应可以提高基于分子内电荷转移(ICT)的辐射衰变过程的效率。制备了六种连接有带有CF 3、F、H、CH 3、C(CH 3 ) 3和OCH 3取代基的官能化联苯基的基于邻碳硼烷基的发光体,并通过多核磁共振波谱进行了充分表征。此外,通过单晶X射线衍射法测定了它们的分子结构,结果揭示了联苯环和邻接环周围几何形状的扭曲。-碳硼烷笼是相似的。所有化合物在刚性状态下均表现出基于 ICT 的发射(77 K 溶液和薄膜)。有趣的是,五种化合物(含CF 3的基团由于其发射极弱而无法测量)在薄膜状态下的量子效率(Φ em )随着修饰末端官能团的给电子能力逐渐增加。联苯部分增加。此外,OCH 3组的非辐射衰变常数 ( k nr )估计为 F 组的十分之一,而辐射衰变常数 ( k r)五种化合物相似。优化后的第一激发态(S 1 )结构的偶极矩(μ)逐渐增加,从CF
Chemodivergent Synthesis of One-Carbon-Extended Alcohols via Copper-Catalyzed Hydroxymethylation of Alkynes with Formic Acid
作者:Xin Jin、Hong-Chen Fu、Mei-Yan Wang、Shouying Huang、Yue Wang、Liang-Nian He、Xinbin Ma
DOI:10.1021/acs.orglett.1c01473
日期:2021.7.2
efficient synthesis of alcohols is a long-standing goal of chemical research. Here an intriguing strategy for the chemodivergent copper-catalyzed hydroxymethylation of alkynes with formic acid and hydrosilane has been developed. By simply tuning the amount of formic acid and reaction temperature, distinct one-carbon-extended primary alcohols, that is, allylicalcohols and β-branched alkyl alcohols, were
Copper‐Catalyzed and Proton‐Directed Selective Hydroxymethylation of Alkynes with CO
<sub>2</sub>
作者:Mei‐Yan Wang、Xin Jin、Xiaofei Wang、Shumei Xia、Yue Wang、Shouying Huang、Ying Li、Liang‐Nian He、Xinbin Ma
DOI:10.1002/anie.202012768
日期:2021.2.19
strategy for copper‐catalyzedhydroxymethylation of alkynes with CO2 and hydrosilane was developed. Switched on/off a proton source, for example, tBuOH, directhydroxymethylation and reductive hydroxymethylation could be triggered selectively, delivering a series of allylic alcohols and homobenzylic alcohols, respectively, with high levels of Z/E, regio‐ and enantioselectivity. Such a selective synthesis
Solvent Dependent Preparation of CuI Nanocrystals and the Catalysis in Sonogashira Coupling Reaction
作者:Manbo Zhang、Lanling Wang、Boxiao Tang、Xingcan Shen、Ruixiang Hu
DOI:10.1002/cjoc.201090327
日期:2010.10
Octahedral and rod‐like γ‐CuInanocrystals have been fabricated by using a mild solution method in water, methanol and ethanol respectively. X‐ray diffraction (XRD) and field emission‐scanning electron microscopy (FE‐SEM) were used to characterize the product. The as‐synthesized CuI demonstrates higher activity for the Sonogashira cross‐coupling of 4‐iodoanisole and phenylacetylene.