Ru(II)-catalyzed chelation-assisted highly regioselective C8-hydroxylation of 1,2,3,4-tretrahydroquinolines has been developed. Various 1,2,3,4-tetrahydroquinolines underwent smooth C8–H hydroxylation with cheap and safe K2S2O8 as the oxidant and oxygen source to furnish the corresponding products in good to excellent yields with high tolerance of the functional groups. The choice of a readily installable
已经开发了Ru(II)催化的1,2,3,4-四氢喹啉的螯合辅助的高区域选择性C8-羟基化反应。各种1,2,3,4-四氢喹啉经过顺畅的C8–H羟基化反应,并以廉价且安全的K 2 S 2 O 8作为氧化剂和氧源,以高收率和高官能度耐受性提供了相应的产品。选择易于安装和拆卸的N-嘧啶导向基团是催化的关键。机理研究表明六元钌循环中间体参与了催化循环。该方法还可以扩展到其他(杂)芳烃CH键的直接羟基化反应。
Palladium-Catalyzed Regioselective Decarboxylative Alkylation of Arenes and Heteroarenes with Aliphatic Carboxylic Acids
作者:Chanchal Premi、Ankit Dixit、Nidhi Jain
DOI:10.1021/acs.orglett.5b00878
日期:2015.6.5
An unprecedented Pd(OAc)2-catalyzed decarboxylative alkylation of unactivated arenes, with aliphatic carboxylicacids as inexpensive alkyl sources, is reported. The alkylation, controlled by the directing group, is regioselective, shows high functional group tolerance, and provides mild access to alkylated indolines, 2-phenylpyridines, and azobenzenes under solvent-free conditions in moderate to high
A cobalt(III)-catalyzed C-8 selective C–H amidation of quinoline N-oxide using dioxazolone as an amidating reagentundermildconditions is disclosed. The reaction proceeds efficiently with excellent functional group compatibility. The utility of the current method is demonstrated by gram scale synthesis of C-8 amide quinoline N-oxide and by converting this amidated product into functionalized quinolines
Ruthenium-catalyzed site-selective C7-acyloxyation of indolines with carboxylic acids is presented that can be oxidized to indoles with diverse functional groups.
铑催化的选择性C7-酰氧化反应将吲哚与羧酸进行作用,可氧化为具有多种功能基团的吲哚化合物。
Predictable site-selective functionalization: Promoter group assisted <i>para</i>-halogenation of <i>N</i>-substituted <b>(</b>hetero<b>)</b>aromatics under metal-free condition
SEAr (electrophilic aromatic substitution) type reaction is disclosed. SEAr type reaction has been utilized for the C5-bromination of indolines (para-selective) with N-bromosuccinimide under metal and additive-free conditions in good to excellent yields. The developed methodology is also applicable for iodination and challenging chlorination. The pyrimidyl group is identified as a reactivity tuner
本文公开了通过 S E Ar(亲电芳族取代)型反应对N-嘧啶基(杂)芳烃进行区域选择性对-C-H 卤化。S E Ar 型反应已用于二氢吲哚的 C5-溴化(对位选择性)与N-溴代琥珀酰亚胺在无金属和无添加剂的条件下具有良好至极好的收率。所开发的方法也适用于碘化和具有挑战性的氯化。嘧啶基被确定为反应性调节剂,它也控制区域选择性。本方法也适用于苯胺、吡啶、吲哚、羟吲哚、吡唑、四氢喹啉、异喹啉和咔唑的选择性卤化。Fukui 亲核性和自然电荷图等 DFT 研究也支持观察到的p-选择性。标题化合物后官能化为相应的芳基化、烯化和二卤化产物是通过一锅两步的方式实现的。还对药物/天然分子(哈明、依托考昔、可乐定和氯唑沙宗)进行了后期 C-H 溴化,以证明所开发方案的适用性。