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1.
Jian Wen Dingyi Wang Jiasheng Qian Di Wang Chendan Zhu Yue Zhao Zhuangzhi Shi 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(7):2100-2104
Transition‐metal‐mediated metalation of an aromatic C?H bond that is adjacent to a tertiary phosphine group in arylphosphines via a four‐membered chelate ring was first discovered in 1968. Herein, we overcome a long‐standing problem with the ortho‐C?H activation of arylphosphines in a catalytic fashion. In particular, we developed a rhodium‐catalyzed ortho‐selective C?H borylation of various commercially available arylphosphines with B2pin2 through PIII‐chelation‐assisted C?H activation. This discovery is suggestive of a generic platform that could enable the late‐stage modification of readily accessible arylphosphines. 相似文献
2.
Omar Sadek Arnaud Le Gac Nereida Hidalgo Sonia Mallet-Ladeira Karinne Miqueu Ghenwa Bouhadir Didier Bourissou 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2022,134(1):e202110102
Spectacular progress has recently been achieved in transition metal-catalyzed C?H borylation of phosphines as well as directed electrophilic C?H borylation. As shown here, P-directed electrophilic borylation provides a new, straightforward, and efficient access to phosphine–boranes. It operates under metal-free conditions and leverages simple, readily available substrates. It is applicable to a broad range of backbones (naphthyl, biphenyl, N-phenylpyrrole, binaphthyl, benzyl, naphthylmethyl) and gives facile access to various substitution patterns at boron (by varying the boron electrophile or post-derivatizing the borane moiety). NMR monitoring supports the involvement of P-stabilized borenium cations as key intermediates. DFT calculations reveal the existence and stabilizing effect of π-arene/boron interactions in the (biphenyl)(i-Pr)2P→BBr2+ species. 相似文献
3.
Stereoselective CH Borylations of Cyclopropanes and Cyclobutanes with Silica‐Supported Monophosphane–Ir Catalysts 下载免费PDF全文
Ryo Murakami Kiyoshi Tsunoda Dr. Tomohiro Iwai Prof. Dr. Masaya Sawamura 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(41):13127-13131
Heteroatom‐directed C?H borylation of cyclopropanes and cyclobutanes was achieved with silica‐supported monophosphane–Ir catalysts. Borylation occurred at the C?H bonds located γ to the directing N or O atoms with exceptional cis stereoselectivity relative to the directing groups. This protocol was applied to the borylation of a tertiary C?H bond of a ring‐fused cyclopropane. 相似文献
4.
Nickel‐Catalyzed Decarbonylative Borylation of Amides: Evidence for Acyl C−N Bond Activation 下载免费PDF全文
Jiefeng Hu Dr. Yue Zhao Jingjing Liu Yemin Zhang Prof. Dr. Zhuangzhi Shi 《Angewandte Chemie (International ed. in English)》2016,55(30):8718-8722
A nickel/N‐heterocyclic carbene catalytic system has been established for decarbonylative borylation of amides with B2nep2 by C?N bond activation. This transformation shows good functional‐group compatibility and can serve as a powerful synthetic tool for late‐stage borylation of amide groups in complex compounds. More importantly, as a key intermediate, the structure of an acyl nickel complex was first confirmed by X‐ray analysis. Furthermore, the decarbonylative process was also observed. These findings confirm the key mechanistic features of the acyl C?N bond activation process. 相似文献
5.
Dr. Shubhankar Kumar Bose Andrea Deißenberger Antonius Eichhorn Prof. Dr. Patrick G. Steel Prof. Dr. Zhenyang Lin Prof. Dr. Todd B. Marder 《Angewandte Chemie (International ed. in English)》2015,54(40):11843-11847
A zinc‐catalyzed combined C? X and C? H borylation of aryl halides using B2pin2 (pin=OCMe2CMe2O) to produce the corresponding 1,2‐diborylarenes under mild conditions was developed. Catalytic C? H bond activation occurs ortho to the halide groups if such a site is available or meta to the halide if the ortho position is already substituted. This method thus represents a novel use of a group XII catalyst for C? H borylation. This transformation does not proceed via a free aryne intermediate, but a radical process seems to be involved. 相似文献
6.
Xiaodong Qiu Panpan Wang Dingyi Wang Minyan Wang Yu Yuan Zhuangzhi Shi 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(5):1518-1522
Rhodium‐catalyzed C7‐selective decarbonylative arylation, olefination, and methylation of indoles with carboxylic acids or anhydrides by C?H and C?C bond activation have been developed. Furthermore, C7‐acylation products can also be generated selectively at a lower reaction temperature in the developed system. The key to the high reactivity and regioselectivity of this transformation is the appropriate choice of an indole N‐PtBu2 chelation‐assisted group. This method has many advantages, including easy access and removal of the directing group, the use of cheap and widely available coupling agents, no requirement of an external ligand or oxidant, a broad substrate scope, high efficiency, and the formation of a sole regioisomer. 相似文献
7.
Xiaodong Qiu Panpan Wang Dingyi Wang Minyan Wang Yu Yuan Zhuangzhi Shi 《Angewandte Chemie (International ed. in English)》2019,58(5):1504-1508
Rhodium‐catalyzed C7‐selective decarbonylative arylation, olefination, and methylation of indoles with carboxylic acids or anhydrides by C?H and C?C bond activation have been developed. Furthermore, C7‐acylation products can also be generated selectively at a lower reaction temperature in the developed system. The key to the high reactivity and regioselectivity of this transformation is the appropriate choice of an indole N‐PtBu2 chelation‐assisted group. This method has many advantages, including easy access and removal of the directing group, the use of cheap and widely available coupling agents, no requirement of an external ligand or oxidant, a broad substrate scope, high efficiency, and the formation of a sole regioisomer. 相似文献
8.
Shao‐Tao Bai Charles B. Bheeter Joost N. H. Reek 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(37):13173-13177
Reported is an iridium catalyst for ortho‐selective C?H borylation of challenging secondary aromatic amide substrates, and the regioselectivity is controlled by hydrogen‐bond interactions. The BAIPy ‐Ir catalyst forms three hydrogen bonds with the substrate during the crucial activation step, and allows ortho‐C?H borylation with high selectivity. The catalyst displays unprecedented ortho selectivities for a wide variety of substrates that differ in electronic and steric properties, and the catalyst tolerates various functional groups. The regioselective C?H borylation catalyst is readily accessible and converts substrates on gram scale with high selectivity and conversion. 相似文献
9.
Catalytic Borylation of SCF3‐Functionalized Arenes by Rhodium(I) Boryl Complexes: Regioselective CH Activation at the ortho‐Position 下载免费PDF全文
Dipl.‐Chem. Sabrina I. Kalläne Prof. Dr. Thomas Braun 《Angewandte Chemie (International ed. in English)》2014,53(35):9311-9315
An unprecedented reaction pathway for the borylation of SCF3‐containing arenes using [Rh(Bpin)(PEt3)3] (pin=pinacolato) is reported. Catalytic processes were developed and the functionalizations proceed under mild reaction conditions. The C? H activations occur with a unique regioselectivity for the position ortho to the SCF3 group, which apparently serves as directing group. Borylated SCF3 compounds can serve as versatile building blocks. 相似文献
10.
Site‐Selective CH Borylation of Quinolines at the C8 Position Catalyzed by a Silica‐Supported Phosphane–Iridium System 下载免费PDF全文
Shota Konishi Dr. Soichiro Kawamorita Dr. Tomohiro Iwai Prof. Patrick G. Steel Prof. Dr. Todd B. Marder Prof. Dr. Masaya Sawamura 《化学:亚洲杂志》2014,9(2):434-438
Site‐selective C? H borylation of quinoline derivatives at the C8 position has been achieved by using a heterogeneous Ir catalyst system based on a silica‐supported cage‐type monophosphane ligand SMAP. The efficient synthesis of a corticotropin‐releasing factor1 (CRF1) receptor antagonist based on a late‐stage C? H borylation strategy demonstrates the utility of the C8 borylation reaction. 相似文献
11.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(6):1517-1521
An iridium/bipyridine‐catalyzed ortho ‐selective C−H borylation of aryl sulfides was developed. High ortho ‐selectivity was achieved by a Lewis acid–base interaction between a boryl group of the ligand and a sulfur atom of the substrate. This is the first example of a catalytic and regioselective C−H transformation controlled by a Lewis acid–base interaction between a ligand and a substrate. The C−H borylation reaction could be conducted on a gram scale, and with a bioactive molecule as a substrate, demonstrating its applicability to late‐stage regioselective C−H borylation. A bioactive molecule was synthesized from an ortho ‐borylated product by converting the boryl and methylthio groups of the product. 相似文献
12.
A mild and efficient C(sp2)?H nitration of 3‐substituted indoles, by using the economical and non‐toxic cobalt nitrate hexahydrate [Co(NO3)2 ? 6 H2O] as a catalyst and tert‐butyl nitrite (TBN) as the nitro source, is reported. This approach provides a unique methodology involving a site‐selective C?N bond formation for preparation of C‐2 substituted nitro indoles. Utilization of the tBoc as the removable directing group enhances the synthetic utility of the method. 相似文献
13.
Catalyst‐Controlled Regiodivergent CH Borylation of Multifunctionalized Heteroarenes by Using Iridium Complexes 下载免费PDF全文
Dr. Ikuo Sasaki Jumpei Taguchi Shotaro Hiraki Prof. Dr. Hajime Ito Dr. Tatsuo Ishiyama 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(25):9236-9241
The regiodivergent C?H borylation of 2,5‐disubstituted heteroarenes with bis(pinacolato)diboron was achieved by using iridium catalysts formed in situ from [Ir(OMe)(cod)]2/dtbpy (cod=1,5‐cyclooctadiene, dtbpy: 4,4′‐di‐tert‐butyl‐2,2′‐bipyridine) or [Ir(OMe)(cod)]2/2 AsPh3. When [Ir(OMe)(cod)]2/dtbpy was used as the catalyst, borylation at the 4‐position proceeded selectively to afford 4‐borylated products in high yields (dtbpy system A). The regioselectivity changed when the [Ir(OMe)(cod)]2/2 AsPh3 catalyst was used; 3‐borylated products were obtained in high yields with high regioselectivity (AsPh3 system B). The regioselectivity of borylation was easily controlled by changing the ligands. This reaction was used in the syntheses of two different bioactive compound analogues by using the same starting material. 相似文献
14.
Kazuishi Fukuda Nobuharu Iwasawa Jun Takaya 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(9):2876-2879
Efficient, phosphine‐directed ortho C?H borylation of arylphosphine derivatives was achieved using Ru catalysts for the first time. The reaction is applicable to various tertiary arylphosphine and arylphosphinite derivatives to give (o‐borylaryl)phosphorus compounds in high yields. This reaction enables easy access to a variety of functionalized phosphine ligands and ambiphilic phosphine boronate compounds, thus realizing a new late‐stage modification of phosphorus compounds. 相似文献
15.
Iridium‐Catalyzed,Silyl‐Directed,peri‐Borylation of C−H Bonds in Fused Polycyclic Arenes and Heteroarenes 下载免费PDF全文
Dr. Bo Su Prof. Dr. John F. Hartwig 《Angewandte Chemie (International ed. in English)》2018,57(32):10163-10167
peri‐Disubstituted naphthalenes exhibit interesting physical properties and unique chemical reactivity, due to the parallel arrangement of the bonds to the two peri‐disposed substituents. Regioselective installation of a functional group at the position peri to 1‐substituted naphthalenes is challenging due to the steric interaction between the existing substituent and the position at which the second one would be installed. We report an iridium‐catalyzed borylation of the C?H bond peri to a silyl group in naphthalenes and analogous polyaromatic hydrocarbons. The reaction occurs under mild conditions with wide functional group tolerance. The silyl group and the boryl group in the resulting products are precursors to a range of functional groups bound to the naphthalene ring through C?C, C?O, C?N, C?Br and C?Cl bonds. 相似文献
16.
Isaac Choi Antonis M. Messinis Lutz Ackermann 《Angewandte Chemie (International ed. in English)》2020,59(30):12534-12540
C7?H‐functionalized indoles are ubiquitous structural units of biological and pharmaceutical compounds for numerous antiviral agents against SARS‐CoV or HIV‐1. Thus, achieving site‐selective functionalizations of the C7?H position of indoles, while discriminating among other bonds, is in high demand. Herein, we disclose site‐selective C7?H activations of indoles by ruthenium(II) biscarboxylate catalysis under mild conditions. Base‐assisted internal electrophilic‐type substitution C?H ruthenation by weak O‐coordination enabled the C7?H functionalization of indoles and offered a broad scope, including C?N and C?C bond formation. The versatile ruthenium‐catalyzed C7?H activations were characterized by gram‐scale syntheses and the traceless removal of the directing group, thus providing easy access to pharmaceutically relevant scaffolds. Detailed mechanistic studies through spectroscopic and spectrometric analyses shed light on the unique nature of the robust ruthenium catalysis for the functionalization of the C7?H position of indoles. 相似文献
17.
Jian He Heng Jiang Ryosuke Takise Ru‐Yi Zhu Dr. Gang Chen Prof. Dr. Hui‐Xiong Dai Dr. T. G. Murali Dhar Dr. Jun Shi Dr. Hao Zhang Dr. Peter T. W. Cheng Prof. Dr. Jin‐Quan Yu 《Angewandte Chemie (International ed. in English)》2016,55(2):785-789
A quinoline‐based ligand effectively promotes the palladium‐catalyzed borylation of C(sp3)? H bonds. Primary β‐C(sp3)? H bonds in carboxylic acid derivatives as well as secondary C(sp3)? H bonds in a variety of carbocyclic rings, including cyclopropanes, cyclobutanes, cyclopentanes, cyclohexanes, and cycloheptanes, can thus be borylated. This directed borylation method complements existing iridium(I)‐ and rhodium(I)‐catalyzed C? H borylation reactions in terms of scope and operational conditions. 相似文献
18.
Dr. Lanting Xu Chao Zhang Dr. Yupeng He Dr. Lushi Tan Prof. Dr. Dawei Ma 《Angewandte Chemie (International ed. in English)》2016,55(1):321-325
An efficient rhodium‐catalyzed method for direct C? H functionalization at the C7 position of a wide range of indoles has been developed. Good to excellent yields of alkenylation products were observed with acrylates, styrenes, and vinyl phenyl sulfones, whereas the saturated alkylation products were obtained in good yield with α,β‐unsaturated ketones. Both the N‐pivaloyl directing group and the rhodium catalyst proved to be crucial for high regioselectivity and conversion. 相似文献
19.
Ruthenium(II)‐Catalyzed C−H Activation of Imidamides and Divergent Couplings with Diazo Compounds: Substrate‐Controlled Synthesis of Indoles and 3H‐Indoles 下载免费PDF全文
Yunyun Li Dr. Zisong Qi Dr. He Wang Xifa Yang Prof. Xingwei Li 《Angewandte Chemie (International ed. in English)》2016,55(39):11877-11881
Indoles are an important structural motif that is commonly found in biologically active molecules. In this work, conditions for divergent couplings between imidamides and acceptor–acceptor diazo compounds were developed that afforded NH indoles and 3H‐indoles under ruthenium catalysis. The coupling of α‐diazoketoesters afforded NH indoles by cleavage of the C(N2)?C(acyl) bond whereas α‐diazomalonates gave 3H‐indoles by C?N bond cleavage. This reaction constitutes the first intermolecular coupling of diazo substrates with arenes by ruthenium‐catalyzed C?H activation. 相似文献
20.
Stereodivergent Synthesis of Arylcyclopropylamines by Sequential CH Borylation and Suzuki–Miyaura Coupling 下载免费PDF全文
Shin Miyamura Misaho Araki Prof. Dr. Takayoshi Suzuki Prof. Dr. Junichiro Yamaguchi Prof. Dr. Kenichiro Itami 《Angewandte Chemie (International ed. in English)》2015,54(3):846-851
A step‐economical and stereodivergent synthesis of privileged 2‐arylcyclopropylamines (ACPAs) through a C(sp3)? H borylation and Suzuki–Miyaura coupling sequence has been developed. The iridium‐catalyzed C? H borylation of N‐cyclopropylpivalamide proceeds with cis selectivity. The subsequent B‐cyclopropyl Suzuki–Miyaura coupling catalyzed by [PdCl2(dppf)]/Ag2O proceeds with retention of configuration at the carbon center bearing the Bpin group, while epimerization at the nitrogen‐bound carbon atoms of both the starting materials and products is observed under the reaction conditions. This epimerization is, however, suppressed in the presence of O2. The present new ACPA synthesis results in not only a significant reduction in the steps required for making ACPA derivatives, but also the ability to access either isomer (cis or trans) by simply changing the atmosphere (N2 or O2) in the coupling stage. 相似文献