Solvatochromism, acidochromism and aggregation-induced emission of propeller-shaped spiroborates
作者:Kang Li、Jichun Cui、Zeren Yang、Yanmin Huo、Wenzeng Duan、Shuwen Gong、Zhipeng Liu
DOI:10.1039/c8dt03374a
日期:——
Propeller-shaped pyridyl-enolato-catecholate/-salicyl spiroborates (Sborepy1–6) were synthesized. The complexes Sborepy3–6 show weak emission in fluid solution and aggregation-induced emission enhancement in the aggregation state with large Stokes shifts of 4025–5237 cm−1. Moreover, intense solid-state emissions with high Φf ranging from 25% to 37% were observed for Sborepy3–6 owing to the weak intermolecular
合成了螺旋形的吡啶基-烯醇-邻苯二酚/水杨基螺硼酸酯(Sborepy1-6)。Sborepy3-6配合物在流体溶液中显示出微弱的发射,并且在聚集状态下发生聚集诱导的发射增强,斯托克斯位移为4025-5237 cm -1时有很大的变化。此外,具有高激烈固态排放Φ ˚F观察用于测距从25%到37%Sborepy3-6由于在其固态弱的分子间相互作用。通过以下方式揭示了AIE和强烈的固态发射X射线衍射分析和理论计算。此外,还证明了溶液状态下的溶剂变色作用以及在Sborepy3和Sborepy6固态下作为荧光酸性蒸气传感器的潜在应用。
Axially chiral propeller-shaped spiroborates with aggregation-modulated circularly polarized luminescence
作者:Wenzeng Duan、Kang Li、Honghan Ji、Yanmin Huo、Qingxia Yao、Houting Liu、Shuwen Gong
DOI:10.1016/j.dyepig.2021.109538
日期:2021.9
challenge in developing chiroptical small organic molecules (SOMs) materials. We herein report a series of axially chiral propeller-shaped pyridyl-/benzothiazolyl-enolato-naphtholate spiroborates ((R)-/(S)-2a-2d). Of these spiroborates, the CPL signals of (R)-/(S)-2c-2d could be effectively modulated by increasing water fraction (fw) from 50% to 90% in the THF-H2O solution. (R)-/(S)-2c exhibit aggregation-amplified
用大的发光不对称因子和反转信号调制 CPL 是开发手性有机小分子 (SOM) 材料的一大挑战。我们在此报告了一系列轴向手性螺旋桨形吡啶基-/苯并噻唑基-烯醇基-萘酚盐螺硼酸盐 (( R ) -/ ( S )- 2a - 2d )。这些spiroborates的,(的CPL信号[R )- /(小号) - 2C - 2d中,可以有效地通过增加水分数(调制˚F瓦特)从50%至90%在THF-H 2 O解决方案。( R ) -/( S )- 2c表现出聚集放大的 CPL,不对称因子 ( g lum ) 高达 2.38 × 10 -2并且 ( R ) -/ ( S )- 2d表现出聚集诱导的 CPL。此外, ( R ) -/ ( S )- 2c的 CPL 信号表现出可逆反转,f w从 50% 增加到 90%。CPL 信号的放大和反转通过扫描电子显微镜 (SEM) 图像观察到的螺旋自组装和发射分子内电荷转移
A Mild and Efficient Synthesis of Pyrazolo[1,5-a]pyridines Mediated by Triphenylphosphine/Diiodine
A synthesis of 2,3-diaryl-substituted pyrazolo[1,5-a]pyridines in moderate to good yields under metal-free and mild conditions is described. The intramolecular cyclization of the oxime substrates is mediated by PPh3/I2, which leads directly to pyrazolo[1,5-a]pyridines without the formation of a 2H-azirine intermediate. Various substituents on the aryl rings are compatible with the method.
Reactivity of 2-benzylpyridyl lithium toward benzonitrile derivatives: Addition versus elimination
作者:Xiaomin Hao、Lu Qin、Mali Xu、Xia Chen
DOI:10.1016/j.jorganchem.2017.10.042
日期:2017.12
hydrolysis product 2-benzylpyridyl-ketone 2–5, respectively, in which the reaction involved in a 1,3-shift of -SiMe3 group to form a dimeric pyridyl-1-aza-allyl-lithium then followed by acidic hydrolysis. The MeOLi elimination reaction between Li2 and p-MeO(C6H4)CN resulted in formation of 4-(2-benzylpyridyl)benzonitrile 6. The reaction of Li2 with p-Me(C6H4)CN in the presence of TMEDA generated a 1:2 hydrolysis
这项工作研究了2-苄基吡啶基锂(2-Pyr)C(Ph)(R)Li(R = SiMe 3,Li1 ; R = H,Li2)对苯甲腈衍生物的反应性。基于不同的产物,锂盐与腈之间的反应可能分别涉及加成,消除和双分子偶联途径。用ArCN(Ar = Ph,p -Tolyl,o -Tolyl,p -OMePh)处理Li1得到加成中间体吡啶基-1-氮杂-烯丙基-锂[(2-Pyr)C(Ph)C(Ar) N(SiMe 3)} Li] 2(1, Ar = Ph)及其相应的水解产物2-苄基吡啶基酮2 –分别参见图5,其中反应涉及-SiMe 3基团的1,3-转移以形成二聚吡啶基-1-氮杂-烯丙基-锂,然后进行酸性水解。之间的MeOLi消除反应LI2和p -MeO(C 6 H ^ 4)CN导致形成4-(2-苄基吡啶基)苄腈6。的反应LI2与p -Me(C 6 H ^ 4)CN在TMEDA的存在下产生的1:2加合物