School of Chemistry, Chemical Engineering and Life Science, Wuhan University of Technology, 205 Luoshi Road, 430070, Wuhan, China.
Chemistry. 2018 Sep 18;24(52):13744-13748. doi: 10.1002/chem.201802269. Epub 2018 Aug 21.
A simple and efficient method for transition-metal-free N-arylation of various amines by triarylsulfonium triflates is described. Both aliphatic and aromatic amines were smoothly converted at 80 °C in the presence of tBuOK or KOH to give the corresponding mono N-arylated products in good to high yields. The molar ratios of the reactants and the choice of bases had a big effect on the reaction. When a large excess of [Ph S][OTf] and tBuOK were employed for primary amines under the standard conditions, the bis(N-phenyl) products were predominantly formed. This method was also applicable to the synthesis of bioactive N-phenyl amino acid derivatives. The control experiments, the deuterium labelling study, and the presence of regioisomers of N-arylated products when using 4-substituted triarylsulfonium triflates suggested that the reaction might proceed through an aryne intermediate. The present protocol demonstrated that triarylsulfonium salts are versatile arylation reagents in the construction of C -N bonds.
本文描述了一种简单高效的三芳基锍三氟甲磺酸酯促进的各种胺的无过渡金属 N-芳基化方法。脂肪族和芳香族胺在 80°C 下，在 tBuOK 或 KOH 的存在下，顺利地转化为相应的单 N-芳基化产物，产率良好至高产率。反应物的摩尔比和碱的选择对反应有很大的影响。当在标准条件下，使用过量的[PhS][OTf]和 tBuOK 对伯胺进行反应时，主要生成双（N-苯基）产物。该方法也适用于生物活性 N-芳基氨基酸衍生物的合成。控制实验、氘标记研究以及使用 4-取代的三芳基锍三氟甲磺酸酯时 N-芳基化产物的区域异构体的存在表明，反应可能通过芳基炔中间体进行。本方案证明了三芳基锍盐是构建 C-N 键的多功能芳基化试剂。
