Metal-free C–H alkylation of heteroarenes with alkyltrifluoroborates: a general protocol for 1°, 2° and 3° alkylation
作者:Jennifer K. Matsui、David N. Primer、Gary A. Molander
DOI:10.1039/c7sc00283a
日期:——
A photoredox-catalyzed C–H functionalization of heteroarenes using a variety of primary, secondary, and tertiary alkyltrifluoroborates is reported. Using Fukuzumi's organophotocatalyst and a mild oxidant, conditions amenable for functionalizing complex heteroaromatics are described, providing a valuable tool for late-stage derivatization. The reported method addresses the three major limitations of
据报道,使用各种伯,仲和叔烷基三氟硼酸酯进行光氧化还原催化的杂芳烃的CH官能化。描述了使用Fukuzumi的有机光催化剂和温和的氧化剂,适合于功能化复杂杂芳族化合物的条件,为后期衍生化提供了有价值的工具。报告的方法解决了先前报道的光氧化还原介导的Minisci反应的三个主要局限性:(1)使用超化学计量的自由基前体,(2)反复选择性,以及(3)引入昂贵的光催化剂。另外,使用了许多前所未有的复杂烷基,从而增加了Minisci化学可利用的化学空间。为了展示后期功能化中的应用程序,合成了奎宁和喜树碱类似物。最后,进行了NMR研究以提供合理的杂芳基活化作用,该活化作用允许使用单当量的自由基前体,并且还提高了区域选择性。因此,在酸催化剂和BF 3的存在下观察到1 H和13 C NMR观察到独特的杂芳基物质。
A novel iridium/acid co-catalyzed transfer hydrogenative C(sp<sup>3</sup>)–H bond alkylation to access functionalized N-heteroaromatics
作者:Zhenda Tan、Huanfeng Jiang、Min Zhang
DOI:10.1039/c6cc03996k
日期:——
A novel iridium/acid co-catalysed transfer hydrogenative coupling strategy, enabling direct alkylation of C(sp3)-H bond and atom-economic access to alkyl chain-lengthened N-Heteroaromatics from six-membered 2-alkyl cyclicamines and aldehydes, has been...
Spiro‐Bicyclic Bisborane Catalysts for Metal‐Free Chemoselective and Enantioselective Hydrogenation of Quinolines
作者:Xiang Li、Jun‐Jie Tian、Ning Liu、Xian‐Shuang Tu、Ning‐Ning Zeng、Xiao‐Chen Wang
DOI:10.1002/anie.201900907
日期:2019.3.26
A new series of spiro‐bicyclic bisborane catalysts has been prepared by means of hydroboration reactions of C2‐symmetric spiro‐bicyclic dienes with HB(C6F5)2 and HB(p‐C6F4H)2. When used for hydrogenation of quinolines, these catalysts give excellent yields and enantiomeric excesses, and show turnover numbers of up to 460. The most attractive feature of these metal‐free hydrogenation reactions was the
通过C 2对称螺双环二烯与HB(C 6 F 5)2和HB(p C 6 F 4 H)2的硼氢化反应制备了一系列新的螺双环双硼烷催化剂。当用于喹啉加氢时,这些催化剂具有出色的收率和对映体过量,并且显示出高达460的周转率。这些无金属加氢反应的最吸引人的特点是宽泛的官能团耐受性,使该方法可与现有方法互补喹啉加氢的方法。
PROCESS FOR PRODUCTION OF BIS-QUATERNARY AMMONIUM SALT, AND NOVEL INTERMEDIATE
申请人:Okamoto Kuniaki
公开号:US20120130107A1
公开(公告)日:2012-05-24
Object To provide a method for producing a bis-quaternary ammonium salt efficiently and a novel synthetic intermediate thereof.
Solution The present invention relates to a method for producing a bis-quaternary ammonium salt represented by a general formula [3] which comprises reacting a disulfonic acid ester represented by a general formula [1] (in the formula, definitions of two R
1
's and T are as described in claim
1
) with a tertiary amine represented by a general formula [2] (in the formula, definitions of R
3
to R
5
are as described in claim
1
), and a disulfonic acid ester represented by a general formula [1′] (in the formula, two R
16
's represent independently a halogen atom or a C1-C3 fluoroalkyl group, and two m's represent independently an integer of 1 to 5).
Ligand-Free RuCl<sub>3</sub>-Catalyzed Alkylation of Methylazaarenes with Alcohols
作者:Tong-Yu Feng、Hong-Xi Li、David James Young、Jian-Ping Lang
DOI:10.1021/acs.joc.6b03095
日期:2017.4.21
RuCl3 efficiently catalyzes the alkylation of methylquinolines, methylpyridines, 2-methyl-benzooxazoles, and 2-methyl-quinoxalines with alkyl- or aryl-alcohols as alkylating agents. This synthetically useful and atom economical transformation does not require additional ligands. The mechanistic study indicated the alkylation reaction underwent a stepwise transfer hydrogenation, aldol condensation,