Palladium(0) nanoparticle-catalyzed sp2 C–H activation: a convenient route to alkyl–aryl ketones by direct acylation of aryl bromides and iodides with aldehydes
作者:Laksmikanta Adak、Sukalyan Bhadra、Brindaban C. Ranu
DOI:10.1016/j.tetlet.2010.05.067
日期:2010.7
Palladium(0) nanoparticles efficiently catalyze aliphatic aldehyde C–H functionalization by aryl halides to produce alkyl–arylketones in good yields. A wide range of substituted aryl and hetero-aryl bromides/iodides and open-chain aldehydes of varied chain length participated in this reaction.
converted with full regioselectivity into the corresponding arylketones by formal hydration of the triple bond under weak acidic conditions, at times and temperatures (≤95 °C) comparable to those used for terminal alkynes. The process catalyzed by Fe2(SO4)3nH2O in glacial acetic acid exhibits good functional group compatibility, including that with bulky triple bond substituents, and can be extended to
在弱酸性条件下,在与终端炔烃相当的时间和温度(≤95°C)下,通过三键的正式水合,烷基芳基炔烃具有完全的区域选择性,从而转化为相应的芳基酮。Fe 2(SO 4)3 n H 2催化的过程冰乙酸中的O具有良好的官能团相容性,包括具有庞大的三键取代基的官能团相容性,并且可以通过去甲硅烷基化水合序列扩展为芳基三甲基甲硅烷基乙炔一锅转化为乙酰基衍生物的过程。总体反应模式以及质子亲和力数据表明,三键是通过质子转移而不是通过与金属离子的π相互作用激活的。该机理特征与贵金属催化剂的机理不同,解释了Fe 2(SO 4)3 n H 2 O / AcOH催化体系表现出的总区域选择性和对空间位阻的不敏感性。
New approach to the synthesis of 2,2':5',2''-terthiophene-5,5''-and 2,2':5',2'':5'',2'''-quaterthiophene-5,5'''-dicarboxylic acids
作者:Anastasia S. Kostyuchenko、Evgeny B. Ulyankin、Anton L. Shatsauskas、Vladislav Yu. Shuvalov、Alexander S. Fisyuk
DOI:10.1007/s10593-018-2386-8
日期:2018.11
further used in reaction with ethyl thioglycolate in the presence of sodium ethoxide, giving ester of 3,3''-decyl-2,2':5',2''-terthiophene-5,5''-dicarboxylic acid. Alkaline hydrolysis of the obtained esters led to the corresponding 2,2':5',2'':5'',2'''-quaterthiophene-5,5'''- and 2,2':5',2''-terthiophene-5,5''-dicarboxylic acids.
Synthesis, polymerization and characterization of substituted dithieno[3,4-b:3′,4′-d]thiophenes
作者:Seiji Inaoka、David M. Collard
DOI:10.1039/a900075e
日期:——
Chemical or electrochemical oxidation of substituted dithieno[3,4-b:3â²,4â²-d]thiophenes provides polymers with defined regiochemical structures. These materials have lower bandgaps (0.7-0.9 eV) than the unsubstituted fused heteroarene. Potential cycling of the 1,3-dimethyl substituted polymer film shows repetitive p- and n-dopability. The chemically-prepared dioctyl analog is soluble in common solvents such as chloroform, dichloromethane and THF. However, overoxidation of the polymers at an electrode surface presents a limitation to the polymerization of substituted analogs of the parent fused heteroarene.
the application of pyrene derivatives as organic semiconductors, but 1,8‐subsituted pyrene semiconductors are less well‐developed. Two p‐type 1,8‐substituted pyrene derivatives were synthesized that were composed of a pyrene core, thiophene or bithiophene arms, and end‐capped octyl chains. These structures were not completely symmetrical and the dihedral angles between the pyrene core and the adjacent
the衍生物作为有机半导体的应用已有许多报道,但1,8取代的pyr半导体发展较差。合成了两个p型1,8-取代的pyr衍生物,它们由a核,噻吩或联噻吩臂和封端的辛基链组成。这些结构不是完全对称的,并且core核与相邻的噻吩单元之间的二面角具有大约两个度的差。这些材料的场效应性能已在各种介电表面上进行了测试。在SiO 2(PS处理的SiO 2)上具有旋涂聚苯乙烯层的两种材料的性能均优于在SiO 2上具有十八烷基三氯硅烷自组装单层的材料的性能(OTS处理的SiO 2),主要归因于低漏电和高电容PS膜上存在大晶粒。含噻吩的化合物在PS处理的SiO 2上的空穴迁移率高达0.18 cm 2 V -1 s -1,这是含双噻吩化合物的空穴迁移率的45倍,这归因于较低的位阻,较高的结晶度和晶粒大。