Recent Advances in Trifluoromethylation Reactions with Electrophilic Trifluoromethylating Reagents
Recent Advances in Trifluoromethylation Reactions with Electrophilic Trifluoromethylating Reagents
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DOI：
10.1002/chem.201404005
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发表时间：
2014-12-15
影响因子：
4.3
通讯作者：
Postigo, Al
中科院分区：
文献类型：
--
作者：
Barata-Vallejo, Sebastian;Lantano, Beatriz;Postigo, Al
亲电三氟甲基化反应是实现化合物与新发现试剂氟烷基化反应的最新方法，如Togni‘s(1-三氟甲基-1，2-苯并碘-3-(1H)-酮)，Uemoto’s(S-(三氟甲基)二苯并硫代四氟硼酸盐)，Ygupolskii‘s(S-三氟甲基二硫基硫酸盐)，Shreve’s(S-(三氟甲基)二苯并硫杂三氟酸盐)和柴田‘s(三氟甲基亚硫胺盐类)试剂。所有这些试剂都会产生一种亲电的三氟甲基化(CF3+)物种，该物种与亲核试剂发生反应。此外，这些后一种活性物种(即CF3+)可以进行电子转移(ET)过程，提供CF3+自由基，从而将范围扩大到可以进行反应的传统亲核试剂以外的底物。在这篇综述中，我们将讨论不同生物底物家族的三氟甲基化反应，以此来比较试剂的范围和最佳反应条件。尽管不是全部，但其中一些反应需要金属或有机金属催化剂的帮助。有些需要添加剂和催化剂来促进氟烷基化反应，但总是由亲电的三氟甲基化物种引发和进行。
Electrophilic trifluoromethylation reactions have been the latest approach to achieve the fluoroalkylation of compounds with newly-discovered reagents, such as the Togni's (1-trifluoromethyl-1,2-benziodoxol-3-(1 H)-one), Umemoto's (S-(trifluoromethyl) dibenzothiophenium tetrafluoroborate), Yagupolskii's (S-(trifluoromethyldiarylsulfonium salts), Shreeve's (S-(trifluoromethyl) dibenzothiophenium triflate), and Shibata's (trifluoromethylsulfoximine salts) reagents. All these reagents produce an electrophilic trifluoromethylating (CF3+) species that undergoes reaction with nucleophiles. In addition, these latter reactive species (i.e. CF3+) can undergo electron-transfer (ET) processes affording CF3+ radicals that expand the scope to substrates other than conventional nucleophiles that can undergo reaction. In this Review, we shall discuss the trifluoromethylation reactions of diverse families of organic substrates of biological interest as a means to comparing the reagents scope and best reaction conditions. Some, though not all, of these reactions require the assistance of metal or organometallic catalysts. Some require additives and catalysts to promote the fluoroalkylation reaction, but invariably all are initiated and carried out by electrophilic trifluoromethylating species.