An easy three step synthesis of perfluoroalkylated amphetamines
摘要:
A general synthesis of perfluoroalkylated amphetamines is presented. Initially, 1-aryl-1-iodo-2-(perfluoroalkyl)ethylenes are prepared by radical addition of perfluoroalkyl iodides to arylacetylenes. Key step of the reaction sequence is the following dehydroiodination in the presence of n-BuLi to give 1-perfluoroalkyl-2-arylacetylenes in situ, which are reacted with secondary amines to produce perfluoroalkylated enamines in a new one pot procedure. Final hydrogenation yields the desired products in good yields. By using N,N-dibenzylamine or N-benzylamines the corresponding primary and secondary perfluoroalkylated amines are easily available. (C) 2004 Elsevier Ltd. All rights reserved.
Copper-catalyzed fluoroalkylation of alkynes, and alkynyl & vinyl carboxylic acids with fluoroalkyl halides
作者:Jing-Jing Ma、Wen-Bin Yi
DOI:10.1039/c7ob00641a
日期:——
Copper-catalyzed fluoroalkylation of alkynes and alkynyl carboxylic acids has been achieved with high functional-group tolerance and excellent regio- and stereoselectivities. A variety of fluoroalkyl halides including ethyl bromodifluoroacetate can be employed. Additionally, an unprecedented decarboxylative fluoroalkylation of α, β-unsaturated carboxylic acids has been achieved via a radical pathway.
Benzophenone<i>vs</i>. Copper/Benzophenone in Light-Promoted Atom Transfer Radical Additions (ATRAs): Highly Effective Iodoperfluoroalkylation of Alkenes/Alkynes and Mechanistic Studies
作者:Redouane Beniazza、Rachel Atkinson、Christelle Absalon、Frédéric Castet、Sergey A. Denisov、Nathan D. McClenaghan、Dominique Lastécouères、Jean-Marc Vincent
DOI:10.1002/adsc.201600501
日期:2016.9.15
redox processes. Mechanistic investigations using transient absorption spectroscopy revealed that a deactivation pathway of the benzophenone triplet (3BP*) is via its reaction with the methanol solvent. We propose that the generated radicals, in particular .CH2OH, play a key role in the initiation step forming Rf. by reacting with RfI, Rf. then entering a radical chain cycle. 1H NMR studies provided evidence
二苯甲酮2(BP)或光还原性铜(II)络合物1有效促进了末端烯烃和炔烃的碘过氟烷基化。尤其是,在低压汞灯(TLC =薄层色谱,6 W)照射365 nm时,甲醇中1摩尔%的BP可以实现快速反应,并具有出色的反应产率。配合物1和BP 2表现出非常相似的反应性,表明涉及1的反应很可能是由二苯甲酮的光活化过程而不是铜(I)/(II)氧化还原过程控制的。使用瞬态吸收光谱的机理研究表明,二苯甲酮三联体的失活途径(3BP *)是通过其与甲醇溶剂的反应来进行的。我们建议特别是生成的部首。CH 2 OH在形成R f的引发步骤中起关键作用。通过与R f I,R f反应。然后进入一个彻底的连锁循环。1 H NMR研究提供了证据,表明形成了大量(约7%NMR)半缩醛CH 3 OCH 2 OH,即之间可能发生的副产物。CH 2 OH和R ˚F I.最后,DFT计算表明,从三线态-三线态能量传递(TTET)工艺与瞬态吸收研究一致,在反应条件下,将3
Visible light photocatalytic cross-coupling and addition reactions of arylalkynes with perfluoroalkyl iodides
作者:Yelan Xiao、Yuen-Kiu Chun、Shun-Cheung Cheng、Ruoyang Liu、Man-Kit Tse、Chi-Chiu Ko
DOI:10.1039/d0ob01767a
日期:——
of arylalkynes with perfluoroalkyl iodides have been developed. Through slight modifications of the reaction conditions, reactions that are selective for the preparation of the C–C coupling product (perfluoroalkyl alkynes) and the addition products (iodo-perfluoroalkyl substituted alkenes) can be achieved. These reactions work well with different types of alkynes and perfluoroalkyl iodides. As the iodide
The Different Faces of Photoredox Catalysts: Visible-Light-Mediated Atom Transfer Radical Addition (ATRA) Reactions of Perfluoroalkyl Iodides with Styrenes and Phenylacetylenes
作者:Thomas Rawner、Eugen Lutsker、Christian A. Kaiser、Oliver Reiser
DOI:10.1021/acscatal.8b00847
日期:2018.5.4
phenylacetylenes using readily available copper phenanthroline catalyst is reported. In contrast to commonly employed [Ru(bpy)3]Cl2, [Ru(phen)3]Cl2 or fac-Ir(ppy)3, [Cu(dap)2]Cl is capable to convert styrenes to the corresponding perfluoroalkyl tagged ethylbenzenes, pointing toward an additional role of the copper catalyst beyond photoinduced electron transfer. An inner sphere catalytic cycle involving Cu(III)
effective activation of RfI and the improvement of sequential photocatalytic reactions. Moreover, the stronger interaction between the substate and surface of catalyst g-NCNCNx can further improve the photocatalytic activity, comparing to the pristine carbon nitride (g-CNx). Through simple variation of the reaction conditions, the photocatalytic addition or coupling reaction can be achieved effectively
光催化自由基氟烷基化已成为在温和条件下制备有价值的有机氟化合物的重要方法。与基于贵金属配合物或有机染料的均相光催化氟烷基化反应相比,使用不含金属的氮化碳催化剂的多相光催化显示出成本效益、更容易的分离和优异的可回收性。在这项工作中,我们报道了使用异相氰基改性石墨氮化碳(g- NCN CNx)作为光催化剂,可见光诱导的炔烃与全氟烷基碘(R f I)的光催化全氟烷基化。实验和计算研究提出的机制揭示了光诱导 g- NCN中的长寿命三重激发态CNx参与初始双分子电子转移过程,从而有效激活R f I并改善后续光催化反应。此外,与原始氮化碳(g-CNx)相比,催化剂g- NCN CNx的基底和表面之间更强的相互作用可以进一步提高光催化活性。通过简单改变反应条件,可以有效、选择性地实现光催化加成或偶联反应。重要的是,异质 g- NCNCNx光催化剂不仅表现出高性能、反应范围广,而且易于回收并重复使用至少五