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1.
Rebecca M. Demming Stephan C. Hammer Bettina M. Nestl Sebastian Gergel Silvia Fademrecht Jürgen Pleiss Bernhard Hauer 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(1):179-183
The direct enantioselective addition of water to unactivated alkenes could simplify the synthesis of chiral alcohols and solve a long‐standing challenge in catalysis. Here we report that an engineered fatty acid hydratase can catalyze the asymmetric hydration of various terminal and internal alkenes. In the presence of a carboxylic acid decoy molecule for activation of the oleate hydratase from E. meningoseptica, asymmetric hydration of unactivated alkenes was achieved with up to 93 % conversion, excellent selectivity (>99 % ee, >95 % regioselectivity), and on a preparative scale. 相似文献
2.
Rebecca M. Demming Stephan C. Hammer Bettina M. Nestl Sebastian Gergel Silvia Fademrecht Jürgen Pleiss Bernhard Hauer 《Angewandte Chemie (International ed. in English)》2019,58(1):173-177
The direct enantioselective addition of water to unactivated alkenes could simplify the synthesis of chiral alcohols and solve a long‐standing challenge in catalysis. Here we report that an engineered fatty acid hydratase can catalyze the asymmetric hydration of various terminal and internal alkenes. In the presence of a carboxylic acid decoy molecule for activation of the oleate hydratase from E. meningoseptica, asymmetric hydration of unactivated alkenes was achieved with up to 93 % conversion, excellent selectivity (>99 % ee, >95 % regioselectivity), and on a preparative scale. 相似文献
3.
Pu‐Sheng Wang Hua‐Chen Lin Yu‐Jia Zhai Zhi‐Yong Han Liu‐Zhu Gong 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2014,126(45):12414-12417
The first enantioselective α‐allylation of aldehydes with terminal alkenes has been realized by combining asymmetric counteranion catalysis and palladium‐catalyzed allylic C H activation. This method can tolerate a wide scope of α‐branched aromatic aldehydes and terminal alkenes, thus affording allylation products in high yields and with good to excellent levels of enantioselectivity. Importantly, the findings suggest a new strategy for the future creation of enantioselective C H/C H coupling reactions. 相似文献
4.
Chiral Counteranion Strategy for Asymmetric Oxidative C(sp3)H/C(sp3)H Coupling: Enantioselective α‐Allylation of Aldehydes with Terminal Alkenes
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Pu‐Sheng Wang Hua‐Chen Lin Yu‐Jia Zhai Zhi‐Yong Han Prof. Dr. Liu‐Zhu Gong 《Angewandte Chemie (International ed. in English)》2014,53(45):12218-12221
The first enantioselective α‐allylation of aldehydes with terminal alkenes has been realized by combining asymmetric counteranion catalysis and palladium‐catalyzed allylic C? H activation. This method can tolerate a wide scope of α‐branched aromatic aldehydes and terminal alkenes, thus affording allylation products in high yields and with good to excellent levels of enantioselectivity. Importantly, the findings suggest a new strategy for the future creation of enantioselective C? H/C? H coupling reactions. 相似文献
5.
Xiaonan Li Xiaoxu Qi Chuanqi Hou Pinhong Chen Guosheng Liu 《Angewandte Chemie (International ed. in English)》2020,59(39):17239-17244
The first Pd‐catalyzed enantioselective azidation of unactivated alkenes has been established by using readily accessible 1‐azido‐1,2‐benziodoxol‐3(1H)‐one (ABX) as an azidating reagent, which affords a wide variety of structurally diverse 3‐N3‐substituted piperidines in good yields with excellent enantioselectivity. The reaction features good functional‐group compatibility and mild reaction conditions. Notably, both an electrophilic azidating reagent and the sterically bulky chiral pyridinyl‐oxazoline (Pyox) ligand are crucial to the successful reaction. 相似文献
6.
Copper‐Catalyzed Enantioselective Markovnikov Protoboration of α‐Olefins Enabled by a Buttressed N‐Heterocyclic Carbene Ligand
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Yuan Cai Xin‐Tuo Yang Dr. Shuo‐Qing Zhang Feng Li Yu‐Qing Li Lin‐Xin Ruan Prof. Dr. Xin Hong Prof. Dr. Shi‐Liang Shi 《Angewandte Chemie (International ed. in English)》2018,57(5):1376-1380
Reported is a highly enantioselective copper‐catalyzed Markovnikov protoboration of unactivated terminal alkenes. A variety of simple and abundant feedstock α‐olefins bearing a diverse array of functional groups and heterocyclic substituents can be used as substrates, and the reaction proceeds under mild reaction conditions at ambient temperature to provide expedient access to enantioenriched alkylboronic esters in good regioselectivity and with excellent enantiocontrol. Critical to the success of the protocol was the development and application of a novel, sterically hindered N‐heterocyclic carbene, (R,R,R,R)‐ANIPE, as the ligand for copper. 相似文献
7.
Ting Liu Yunhui Yang Congyang Wang 《Angewandte Chemie (International ed. in English)》2020,59(34):14256-14260
Transition‐metal‐catalyzed hydroarylation of unactivated alkenes with strategic use of remote coordinating functional groups has received significant attention recently to address the issues of both low reactivity and poor selectivity. The bidentate 8‐aminoquinoline amide group is the most successfully adopted in unactivated alkenes for Pd and Ni catalysis. We describe the first manganese‐catalyzed hydroarylation of unactivated alkenes bearing diverse simple functionalities with arylboronic acids. A series of δ‐ and γ‐arylated amides, ketones, pyridines, and amines was accessed with excellent regioselectivity and in high yields. Hydroalkenylation of unactivated alkenes was also shown to be applicable under this manganese‐catalysis regime. The method features earth‐abundant manganese catalysis, easily available substrates, broad functional‐group tolerance, and excellent regioselective control. 相似文献
8.
[reaction: see text] Phosphine gold(I) complexes catalyzed isomerization of terminal alkenes and hydroamination of unactivated alkenes under thermal and microwave-assisted conditions. This is the first example of the use of microwave radiation as a heat source for gold(I)-catalyzed organic reactions. 相似文献
9.
An Easily Accessed Nickel Nanoparticle Catalyst for Alkene Hydrosilylation with Tertiary Silanes
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Ivan Buslov Dr. Fang Song Prof. Dr. Xile Hu 《Angewandte Chemie (International ed. in English)》2016,55(40):12295-12299
The first efficient and non‐precious nanoparticle catalyst for alkene hydrosilylation with commercially relevant tertiary silanes has been developed. The nickel nanoparticle catalyst was prepared in situ from a simple nickel alkoxide precatalyst Ni(OtBu)2?x KCl. The catalyst exhibits high activity for anti‐Markovnikov hydrosilylation of unactivated terminal alkenes and isomerizing hydrosilylation of internal alkenes. The catalyst can be applied to synthesize a single terminal alkyl silane from a mixture of internal and terminal alkene isomers, and to remotely functionalize an internal alkene derived from a fatty acid. 相似文献
10.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2018,130(39):13117-13121
We report an asymmetric synthesis of enantioenriched gem‐bis(boryl)alkanes in an enantioselective diborylation of 1,1‐disubstituted alkenes catalyzed by Co(acac)2/(R)‐DM‐segphos. A range of activated and unactivated alkenes underwent this asymmetric diborylation in the presence of cyclooctene as a hydrogen acceptor, affording the corresponding gem‐bis(boryl)alkanes with high enantioselectivity. The synthetic utility of these chiral organoboronate compounds was demonstrated through several stereospecific derivatizations and the synthesis of sesquiterpene and sesquiterpenoid natural products. 相似文献
11.
Jun He Yuhang Xue Bo Han Chunzhu Zhang Dr. You Wang Prof. Shaolin Zhu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(6):2348-2352
Starting from diverse alkene-tethered aryl iodides and O-benzoyl-hydroxylamines, the enantioselective reductive cross-electrophilic 1,2-carboamination of unactivated alkenes was achieved using a chiral pyrox/nickel complex as the catalyst. This mild, modular, and practical protocol provides rapid access to a variety of β-chiral amines with an enantioenriched aryl-substituted quaternary carbon center in good yields and with excellent enantioselectivities. This process reveals a complementary regioselectivity when compared to Pd and Cu catalysis. 相似文献
12.
A simple and efficient method for functionalization of electron-rich arenes and heteroarenes with unactivated alkenes by Au(III)-catalyzed intermolecular hydroarylation under mild reaction conditions was developed. This method features a short reaction time (5 h) under mild conditions and has a broad substrate scope, including electron-rich arenes and heteroarenes, terminal and internal substituted aryl alkenes, and unactivated aliphatic alkenes. 相似文献
13.
Weijie Yu Shengchun Wang Meng He Zhou Jiang Yi Yu Jinping Lan Jin Luo Pengjie Wang Prof. Xiaotian Qi Prof. Tao Wang Prof. Aiwen Lei 《Angewandte Chemie (International ed. in English)》2023,62(17):e202219166
Precisely introducing two similar functional groups into bulk chemical alkenes represents a formidable route to complex molecules. Especially, the selective activation of two electrophiles is in crucial demand, yet challenging for cross-electrophile-coupling. Herein, we demonstrate a redox-mediated electrolysis, in which aryl nitriles are both aryl radical precursors and redox-mediators, enables an intermolecular alkene 1,2-diarylation with a remarkable regioselectivity, thereby avoiding the involvement of transition-metal catalysts. This transformation utilizes cyanoarene radical anions for activating various aryl halides (including iodides, bromides, and even chlorides) and affords 1,2-diarylation adducts in up to 83 % yield and >20 : 1 regioselectivity with more than 80 examples, providing a feasible approach to complex bibenzyl derivatives. 相似文献
14.
Dr. Subramaniyan Mannathan Prof. Dr. Chien‐Hong Cheng 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(37):11771-11777
A cobalt‐catalyzed reductive coupling of terminal alkynes, RC?CH, with activated alkenes, R′CH?CH2, in the presence of zinc and water to give functionalized trans‐disubstituted alkenes, RCH?CHCH2CH2R′, is described. A variety of aromatic terminal alkynes underwent reductive coupling with activated alkenes including enones, acrylates, acrylonitrile, and vinyl sulfones in the presence of a CoCl2/P(OMe)3/Zn catalyst system to afford 1,2‐trans‐disubstituted alkenes with high regio‐ and stereoselectivity. Similarly, aliphatic terminal alkynes also efficiently participated in the coupling reaction with acrylates, enones, and vinyl sulfone, in the presence of the CoCl2/P(OPh)3/Zn system providing a mixture of 1,2‐trans‐ and 1,1‐disubstituted functionalized terminal alkene products in high yields. The scope of the reaction was also extended by the coupling of 1,3‐enynes and acetylene gas with alkenes. Furthermore, a phosphine‐free cobalt‐catalyzed reductive coupling of terminal alkynes with enones, affording 1,2‐trans‐disubstituted alkenes as the major products in a high regioisomeric ratio, is demonstrated. In the reactions, less expensive and air‐stable cobalt complexes, a mild reducing agent (Zn) and a simple hydrogen source (water) were used. A possible reaction mechanism involving a cobaltacyclopentene as the key intermediate is proposed. 相似文献
15.
Michael T. Bovino Timothy W. Liwosz Nicole E. Kendel Dr. Yan Miller Dr. Nina Tyminska Prof. Eva Zurek Prof. Sherry R. Chemler 《Angewandte Chemie (International ed. in English)》2014,53(25):6383-6387
Chiral saturated oxygen heterocycles are important components of bioactive compounds. Cyclization of alcohols onto pendant alkenes is a direct route to their synthesis, but few catalytic enantioselective methods enabling cyclization onto unactivated alkenes exist. Herein reported is a highly efficient copper‐catalyzed cyclization of γ‐unsaturated pentenols which terminates in C? C bond formation, a net alkene carboetherification. Both intra‐ and intermolecular C? C bond formations are demonstrated, thus yielding functionalized chiral tetrahydrofurans as well as fused‐ring and bridged‐ring oxabicyclic products. Transition‐state calculations support a cis‐oxycupration stereochemistry‐determining step. 相似文献
16.
Jun He Yuhang Xue Bo Han Chunzhu Zhang You Wang Shaolin Zhu 《Angewandte Chemie (International ed. in English)》2020,59(6):2328-2332
Starting from diverse alkene‐tethered aryl iodides and O‐benzoyl‐hydroxylamines, the enantioselective reductive cross‐electrophilic 1,2‐carboamination of unactivated alkenes was achieved using a chiral pyrox/nickel complex as the catalyst. This mild, modular, and practical protocol provides rapid access to a variety of β‐chiral amines with an enantioenriched aryl‐substituted quaternary carbon center in good yields and with excellent enantioselectivities. This process reveals a complementary regioselectivity when compared to Pd and Cu catalysis. 相似文献
17.
Peng Xiong Fan Xu Xiang‐Yang Qian Yared Yohannes Dr. Jinshuai Song Prof. Dr. Xin Lu Prof. Dr. Hai‐Chao Xu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(13):4379-4383
A copper‐catalyzed oxidative amination of unactivated internal alkenes has been developed. The Wacker‐type oxidative alkene amination reaction is traditionally catalyzed by a palladium through a mechanism involving aminopalladation and β‐hydride elimination. Replacing the precious and scarce palladium with a cheap and abundant copper for this transformation has been challenging because of the difficulty associated with the aminocupration of internal alkenes. The combination of a simple copper salt, without additional ligand, as the catalyst and Dess–Martin periodinane as the oxidant, promotes efficiently the oxidative amination of allylic carbamates and ureas bearing di‐ and trisubstituted alkenes leading to oxazolidinones and imidazolidinones. Preliminary mechanistic studies suggested a hybrid radical–organometallic mechanism involving an amidyl radical cyclization to form the key C?N bond. 相似文献
18.
Alkenes are versatile compounds that are available on large scales in industry or through chemical synthesis. Selective functionalization of unactivated alkenes in a chemo‐, regio‐, diastereo‐ and enantioselective fashion is a highly sought‐after goal in organic synthesis. Substrate‐directed enantioselective functionalization of unactivated alkenes provides an important strategy to achieve this goal. Using a functional group on the alkene substrate as a native coordinating group, a two‐point binding mode of the substrate to the metal center enables effective control of regio‐, diastereo‐ and enantioselectivities. Through this strategy, a variety of enantioselective functionalization methods have been developed recently. The recent advances in this area are highlighted here. 相似文献
19.
Yong‐Gang Zhang Xiang‐Lei Liu Zeng‐Yang He Xi‐Ming Li Hong‐Jian Kang Prof. Dr. Shi‐Kai Tian 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(10):2765-2769
An unprecedented oxidative arylation reaction of terminal alkenes with simple aroyl hydrazides has been developed under aerobic conditions for the stereoselective synthesis of 1,2‐disubstituted alkenes. A range of aroyl hydrazides underwent palladium/copper‐catalyzed oxidative Mizoroki–Heck reaction with terminal alkenes open to air in a 1:1 mixture of dimethyl sulfoxide and acetonitrile to give structurally diverse 1,2‐disubstituted alkenes in moderate to excellent yields with excellent regio‐ and E‐selectivity. The reaction tolerated a wide variety of functional groups, such as alkoxy, hydroxy, amino, fluoro, chloro, bromo, cyano, nitro, ester, amide, imide, phosphine oxide, and sulfone groups, and, moreover, molecular oxygen and dimethyl sulfoxide were demonstrated to serve as terminal oxidants. This study provides a useful method for the stereoselective synthesis of 1,2‐disubstituted alkenes through direct transformation of the vinylic C?H bonds in terminal alkenes. 相似文献
20.
Ronald Grigg Marie Dowling Maurice W. Jordan Visuvanathar Sridharan 《Tetrahedron》1987,43(24):5873-5886
Hydrazones of aldehydes and ketones undergo intermolecular cycloaddition to electronegative olefins via azomethine imines, formed by a formal 1,2-prototropic shift, in low to moderate yield on heating in xylene or ethanol. In some instances the reaction is diverted to give products derived (at least formally) from an ene reaction. Similar intramolecular cycloadditions occur with unactivated terminal alkenes and alkynes. 相似文献