De Novo Synthesis of Tricyclic 5,5-Benzannulated Spiroketals
作者:Maddali L. N. Rao、Sk Shamim Islam
DOI:10.1021/acs.orglett.1c01109
日期:2021.5.21
The synthesis of tricyclic 5,5-benzannulated spiroketal scaffolds was accomplished from 2′-hydroxyacetophenones and gem-dibromoalkenes involving a one-pot domino strategy. The hitherto unknown transformation afforded the tricyclic 5,5-benzannulated spiroketals as single diastereomers in high yields with a broad substrate scope.
A variety of arylamines are shown to undergo oxidative C–C bond formation using quinone-based chloranil/H+ reagent as the recyclable organic (metal-free) oxidant system to afford benzidines/naphthidines. Arylamines (3°/2°) designed with various substituents were employed to understand the steric as well as electronic preferences of oxidative dimerization, and a mechanism involving amine radical cation
使用基于醌的氯腈/ H +试剂作为可循环使用的有机(无金属)氧化剂体系,可以显示出多种芳基胺进行氧化C-C键形成,以提供联苯胺/萘啶。设计了具有各种取代基的芳胺(3°/ 2°)用于理解氧化二聚作用的空间和电子偏好,并提出了涉及胺自由基阳离子的机理。通过氧化CC偶联获得的四苯基联苯胺衍生物已通过简单的化学转化进一步转化为发射蓝色光的空穴传输材料。这项研究强调了以简单,经济和有效的方式准备新型HTM。
Benzothiazole-Based Fluorophores of Donor−π-Acceptor−π-Donor Type Displaying High Two-Photon Absorption
reactions. All the target chromophores show strong one-photon and two-photon excited emission. The maximum two-photonabsorption (TPA) cross sections δTPA of the prepared derivatives bearing diphenylamino functionalities occur at wavelengths ranging from 760 to 800 nm and are as large as ∼900−1100 GM. One- and two-photonabsorption characteristics of the title dyes have also been investigated by using
作者:Maddali L. N. Rao、Sk Shamim Islam、Priyabrata Dasgupta
DOI:10.1039/d1ob01383a
日期:——
N-alkynylation of electron-withdrawing or protecting group free N-heteroarenes such as indole, carbazole and pyrrole was developed using gem-dibromoalkenes to synthesize ynamines under ligand-free copper-catalyzed domino conditions. The development methodology of ynamines was also applied in the synthesis of enynamines, multi-coupled bis-ynamines, tris-ynamines, and the natural product peyonine, demonstrating
High-Yield Formation of Substituted Tetracyanobutadienes from Reaction of Ynamides with Tetracyanoethylene
作者:Marie Betou、Nicolas Kerisit、Esme Meledje、Yann R. Leroux、Claudine Katan、Jean-François Halet、Jean-Claude Guillemin、Yann Trolez
DOI:10.1002/chem.201402653
日期:2014.7.28
A high‐yielding sequence of [2+2] cycloaddition–retroelectrocyclization of ynamides with tetracyanoethylene (TCNE) is described. The reaction provided tetracyanobutadiene (TCBD) species, which were characterized by various techniques. DFT and TD‐DFT calculations were also performed to complement experimental findings.