We describe a powerful, broadly applicable cross-coupling protocol that enables carbon–carbon bondformation at highly sterically hindered carbon centers (both sp2 and sp3) by employing organocopper reagents under palladium catalysis. Experimental studies and theoretical calculations indicated that the key to the unique reactivity of copper is the relatively low activation energy of the compact transmetalation
Effects of Perpendicular Aryl Groups on Electronic Properties and Complexation of 4,4-Dihydrodithienosilole
作者:Akihiro Tsurusaki、Soichiro Kyushin
DOI:10.1246/bcsj.20190007
日期:2019.6.15
4,4-Dihydrodithienosilole bearing perpendicular Tip groups at the 3,5-positions (1) was synthesized. Compound 1 was characterized by NMR, IR, and mass spectroscopy and X-ray crystallography. The lo...
合成了在 3,5-位 (1) 处带有垂直尖端基团的 4,4-二氢二噻吩并硅氧烷。化合物 1 通过 NMR、IR、质谱和 X 射线晶体学表征。洛...
Versatile Design Principles for Facile Access to Unstrained Conjugated Organoborane Macrocycles
reactions under high dilution conditions. The resulting monodisperse macrocycles provide important insights into the designprinciples necessary for the preparation of new unstrainedmacrocycles with interesting optical and electronic characteristics. The current research also offers a more general approach to conjugated ambipolar B/N macrocycles as a promising new family of (opto)electronic materials.
π-Expanded Borazine: An Ambipolar Conjugated B-π-N Macrocycle
作者:Pangkuan Chen、Roger A. Lalancette、Frieder Jäkle
DOI:10.1002/anie.201203788
日期:2012.8.6
Staying at a B ′N′ B: A highly symmetric cyclic structure in which N donor and B acceptor sites are alternating (see picture) is found for the first ambipolar π‐conjugated B–N macrocycle. The donor–π–acceptor arrangement results in mutual interactions between B and N and a pronounced solvatochromic effect on the emission. The strong luminescence in solution also lends itself to use in anion recognition
Luminescent Quadrupolar Borazine Oligomers: Synthesis, Photophysics, and Two-Photon Absorption Properties
作者:Pangkuan Chen、Ariel S. Marshall、San-Hui Chi、Xiaodong Yin、Joseph W. Perry、Frieder Jäkle
DOI:10.1002/chem.201502268
日期:2015.12.7
A set of monodisperse bent donor–acceptor–donor‐type conjugated borazine oligomers, BnNn+1 (n=1–4), incorporating electron‐rich triarylamine donor and electron‐deficient triarylborane acceptor units has been prepared through an iterative synthetic approach that takes advantage of highly selective silicon–boron and tin–boron exchange reactions. The effect of chain elongation on the electrochemical,
通过迭代合成制备了一组单分散弯曲的供体-受体-供体型共轭硼嗪低聚物,B n N n +1(n = 1–4),其中包含富电子的三芳基胺供体和缺电子的三芳基硼烷受体单元这种方法利用了高度选择性的硅-硼和锡-硼交换反应。研究了链伸长对电化学,单光子和双光子性质以及激发态光动力学的影响。从芳基胺供体以硼为中心的受体位点导致具有高量子产率的排放量强的分子内电荷转移(ICT)(Φ FL> 0.5)在400–500 nm的范围内。溶剂变色效应导致最短成员(n = 1)的溶剂位移大至约70 nm,并随着链伸长而逐渐降低。这些低聚物在可见光谱区具有很强的双光子吸收(2PA),其2PA横截面高达1410 GM(n = 4),宽带激发态吸收(ESA)归因于长寿单重态-单重态和自由基阳离子/阴离子吸收。激发态动力学也显示出对溶剂环境的敏感性。电化学观察和DFT计算(B3LYP / 6-31G *)揭示了HOMO和