已经开发了一种多样化合成呋喃和槟榔呋喃的通用方法,该方法通过在EtOH中回流,通过K 2 CO 3促进烯醇/ 1,3-二羰基化合物与硝基烯烃之间的环化反应来进行。这种简便的方法已成功用于苯并三呋喃衍生物的合成,苯并三呋喃衍生物是有用的空穴传输材料。该程序还提供了直接接触二氧杂[5]螺旋的方法。该反应提供了广泛的底物范围,使用了廉价的碱和对环境无害的溶剂,并且操作简单。
Direct Palladium-Catalyzed C-4 Arylation of Tri-substituted Furans with Aryl Chlorides: An Efficient Access to Heteroaromatics
作者:Hai Yang、Zhishuo Zheng、Jian Zeng、Huajie Liu、Bing Yi
DOI:10.5012/bkcs.2012.33.8.2623
日期:2012.8.20
A series of functionalized furans were synthesized by way of a palladium -catalyzed coupling reaction of 2,3,5trisubstituted furans with aryl chlorides through C-H bond cleavages at C-4position. The feature of the reaction was facilitative preparation of furan derivatives with good functional group tolerance. All reactions gave the desired products in moderate to good yields in the presences of BuAd2P
通过钯催化的2,3,5三取代呋喃与芳基氯通过C-4位CH键断裂的偶联反应合成了一系列功能化呋喃。该反应的特点是便于制备具有良好官能团耐受性的呋喃衍生物。在 BuAd2P 和 t-BuOK 的存在下,在 DMF 中 120 o C 15 小时后,所有反应均以中等至良好的收率得到所需产物。
Ruthenium/TFA-Catalyzed Coupling of Activated Secondary Propargylic Alcohols with Cyclic 1,3-Diones: Furan versus Pyran Ring Formation
consisting of the 16-electron allyl-ruthenium(II) complex [Ru(η3-2-C3H4Me)(CO)(dppf)][SbF6] (dppf = 1,1′-bis(diphenylphosphino)ferrocene) and trifluoroacetic acid (TFA) has been used to promote the coupling between secondary propargylicalcohols and cyclic 1,3-diketones. The nature of the resulting products was found to be dependent on the ring size of the dicarbonyl compound employed. Thus, whereas 6
Synthesis of 4-Acetoxyindoles
and Related Derivatives by Means of Air Oxidation of 4-Oxo-4,5,6,7-tetrahydroindoles
Obtained from Nitroalkenes and Cyclohexane-1,3-diones
A novel method for synthesizing 4-hydroxyindole derivatives from cyclohexane-1,3-diones and nitroalkenes have been developed in which a newly developed air oxidation of 4-oxo-4,5,6,7-tetrahydroindoles is playing a crucial role.
A variety of sequential gold-catalyzedreactions of 1-phenylprop-2-yn-1-ol with 1,3-dicarbonylcompounds are directed towards different outcomes by a suitable choice of the catalytic system, feature of 1,3-dicarbonyl and reaction conditions.
An efficient and highly regio-selective synthesis of fused & substituted furans has been described using Ca(OTf)2 as the catalyst. This tandem process involves alkylation, 5-exo dig cyclisation and isomerization to furnish densely substituted furans under solvent free conditions. A case study of regioselectivity has been demonstrated.