摘要:
Organic molecules bearing chiral sulfur stereocenters exert a great impact on asymmetric catalysis and synthesis, chiral drugs, and chiral materials. Compared with acyclic ones, the catalytic asymmetric synthesis of thio-heterocycles has largely lagged behind due to the lack of efficient synthetic strategies. Here we establish the first modular platform to access chiral thio-oxazolidinones via Pd-catalyzed asymmetric [3+2] annulations of vinylethylene carbonates with sulfinylanilines. This protocol is featured by readily available starting materials, and high enantio- and diastereoselectivity. In particular, an unusual effect of a non-chiral supporting ligand on the diastereoselectivity was observed. Possible reaction mechanisms and stereocontrol models were proposed.
期刊:
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY,2024年146(2):1410-1422 ISSN:0002-7863
通讯作者:
Xiao, Wen-Jing;Chen, JR
作者机构:
[Zhao, Ke; Qu, Wen-Yuan; Xiao, Wen-Jing; Chen, Jia-Rong; Mao, Zhi-Cheng; Zhang, Bin; Xiao, WJ; Li, Tian-Tian; Zhang, Zhihan; Chen, JR] Cent China Normal Univ, Coll Chem, Wuhan 430079, Hubei, Peoples R China.;[Jiang, Min] Hangzhou Normal Univ, Coll Mat Chem & Chem Engn, Hangzhou 310036, Peoples R China.;[Xiao, Wen-Jing; Chen, Jia-Rong; Xiao, WJ; Chen, JR] Wuhan Inst Photochem & Technol, Wuhan 430082, Hubei, Peoples R China.
通讯机构:
[Xiao, WJ; Chen, JR ] C;Cent China Normal Univ, Coll Chem, Wuhan 430079, Hubei, Peoples R China.;Wuhan Inst Photochem & Technol, Wuhan 430082, Hubei, Peoples R China.
摘要:
Alkene radical ions constitute an integral and unique class of reactive intermediates for the synthesis of valuable compounds because they have both unpaired spins and charge. However, relatively few synthetic applications of alkene radical anions have emerged due to a dearth of generally applicable and mild radical anion generation approaches. Precise control over the chemo- and stereoselectivity in alkene radical anion-mediated processes represents another long-standing challenge due to their high reactivity. To overcome these issues, here, we develop a new redox-neutral strategy that seamlessly merges photoredox and copper catalysis to enable the controlled generation of alkene radical anions and their orthogonal enantioselective cyanofunctionalization via distonic-like species. This new strategy enables highly regio-, chemo-, and enantioselective hydrocyanation, deuterocyanation, and cyanocarboxylation of alkenes without stoichiometric reductants or oxidants under visible light irradiation. This protocol provides a new blueprint for the exploration of the transformation potential of alkene radical anions.
摘要:
A visible‐light‐driven four‐component radical relay aminocarbonylation reaction of unactivated alkenes using 4CzIPN as an organic photocatalyst is developed, providing robust access to β‐fluoroalkyl amides with good yields and selectivity under metal‐free conditions. Importantly, this strategy also shows good compatibility with tertiary carbon radicals. Comprehensive Summary Catalytic four‐component radical carbonylation of unactivated alkenes has recently been recognized as a robust protocol for rapid construction of various structurally diverse carbonyl compounds. Given the significance of fluorine‐containing groups, this reaction class has been extensively applied to assembly of a variety of perfluoroalkyl carboxylic acid derivatives by transition metal catalysis. Herein, we report a visible‐light‐driven radical relay 1,2‐perfluoroalkylation aminocarbonylation of unactivated alkenes using CO gas as carbonyl source and 4CzIPN as organic photocatalyst. A wide range of alkenes and amines were well tolerated, providing the valuable β‐perfluoroalkylated amides with generally good yields and high chemoselectivity.
摘要:
Highly efficient three‐component coupling of organic halides, sodium cyanate and amines or alcohols was achieved with a nickel/photoredox dual catalysis system. Significant N‐containing functional compounds, ureas and carbamates, were produced under green and sustainable conditions. Comprehensive Summary Ureas are widely used in drugs, materials and catalysts because of their diamide structure, which can form strong hydrogen bonds. Therefore, it is of great scientific significance to develop efficient and green methods for the synthesis of urea compounds, especially unsymmetrical ureas. Here, we have disclosed novel and highly efficient three‐component coupling reactions of organic halides, sodium cyanate and amines enabled by nickel/photoredox dual catalysis for the preparation of unsymmetrical ureas. The reaction features simple and safe operations, broad substrate scopes, and product diversities. It allows the facile synthesis of N‐aryl/vinyl ureas from readily available, user‐friendly feedstocks under mild conditions (27 examples, 36%—98% yields). In addition, this method is further derived to alcohols as nucleophiles to synthesize a series of carbamates (15 examples, 40%—95% yields). The mechanism experiment shows that the isocyanate produced by the coupling of halide and sodium cyanate may be the key intermediate in this reaction.
摘要:
An asymmetric cascade cyclization of enynamides and alpha-diazoketones to produce chiral bicyclic lactams bearing chiral all-carbon quaternary stereocenters is realized with up to 95% yield, 98% ee, and >19:1 dr. The combination of visible light photoactivation and the relay of gold and N-oxide catalysis in a cascade process enabled the facile generation and controlled assembly of two reactive intermediates, ketene and aza-o-quinone methide. Theoretical calculations revealed a stepwise [4 + 2] cycloaddition mechanism, with the stereochemistry controlled by the amide group of the catalyst. Remarkably, this study presents the first example of chiral N-oxides serving as catalysts for asymmetric ketene cycloaddition and illustrates how a cascade strategy could be a promising means to access significant chiral heterocyclic scaffolds.
摘要:
We developed a facile bottom‐up strategy to synthesize Ni(II)‐incorporated covalent organic framework (LZU‐713@Ni) as heterogeneous all‐in‐one metallaphotoredox catalyst. LZU‐713@Ni showed excellent activity and recyclability in photoredox/nickel‐catalyzed C−O, C−S, and C−P cross‐coupling reactions. The superiority of bottom‐up strategy was exemplified by the increased activity of LZU‐713@Ni compared to both the dual catalyst system and LZU‐713/Ni prepared via post‐synthetic modification. Abstract The construction of an all‐in‐one catalyst, in which the photosensitizer and the transition metal site are close to each other, is important for improving the efficiency of metallaphotoredox catalysis. However, the development of convenient synthetic strategies for the precise construction of an all‐in‐one catalyst remains a challenging task due to the requirement of precise installation of the catalytic sites. Herein, we have successfully established a facile bottom‐up strategy for the direct synthesis of Ni(II)‐incorporated covalent organic framework (COF), named LZU‐713@Ni, as a versatile all‐in‐one metallaphotoredox catalyst. LZU‐713@Ni showed excellent activity and recyclability in the photoredox/nickel‐catalyzed C−O, C−S, and C−P cross‐coupling reactions. Notably, this catalyst displayed a better catalytic activity than its homogeneous analogues, physically mixed dual catalyst system, and, especially, LZU‐713/Ni which was prepared through post‐synthetic modification. The improved catalytic efficiency of LZU‐713@Ni should be attributed to the implementation of bottom‐up strategy, which incorporated the fixed, ordered, and abundant catalytic sites into its framework. This work sheds new light on the exploration of concise and effective strategies for the construction of multifunctional COF‐based photocatalysts.
摘要:
A mild strategy for the synthesis of boron‐handled pyrazoles through photocatalytic cascade radical cyclization of LBRs (Lewis base‐boryl radicals) with vinyldiazo reagents is described here. The reaction starts with the addition of LBRs at diazo site, followed by intramolecular radical cyclization to access a wide range of important boron‐handled pyrazoles in good to excellent yields. Control experiments, together with detailed mechanism studies well explain the observed reactivity. Abstract Vinyldiazo compounds are one of the most important synthons in the construction of a cyclic ring. Most photochemical transformations of vinyldiazo compounds are mainly focusing on utilization of their C═C bond site, while reactions taking place at terminal nitrogen atom are largely unexplored. Herein, a photocatalytic cascade radical cyclization of LBRs with vinyldiazo reagents through sequential B─N/C─N bond formation is described. The reaction starts with the addition of LBRs (Lewis base–boryl radicals) at diazo site, followed by intramolecular radical cyclization to access a wide range of important boron‐handled pyrazoles in good to excellent yields. Control experiments, together with detailed mechanism studies well explain the observed reactivity. Further studies demonstrate the utility of this approach for applications in pharmaceutical and agrochemical research.
摘要:
The synthesis of chiral endocyclic allenes, especially the medium-sized ones, remains a challenge in allene chemistry due to unfavorable tension and difficult stereocontrol. Herein, an efficient protocol for the construction of chiral nine-membered endocyclic allenes via palladium-catalyzed asymmetric cycloaddition/Cope rearrangement relay of vinyl carbonates with activated enynes is highlighted. This process provides rapid access to a variety of chiral nine-membered endocyclic allenes in good yields with excellent enantioselectivities. In particular, a chiral P,S-ligand shows good performance on stereoinduction, generating central and axial chirality in a single transformation, which is rationalized by DFT calculations and by a proposed transition state.
1 Introduction
2 Pd-Catalyzed Asymmetric Cycloaddition/Cope Rearrangement Relay
3 Plausible Mechanism and Stereochemical Outcome
4 Conclusion and Outlook
作者机构:
[Lu, Liang-Qiu; Rao, Li; Wang, Bao-Cheng; Qu, Bao-Le; Xiao, Wen-Jing; Xiong, Fen-Ya] Cent China Normal Univ, Minist Educ, CCNU Ottawa Joint Res Ctr, Coll Chem,Key Lab Pesticide & Chem Biol, 152 Luoyu Rd, Wuhan 430079, Hubei, Peoples R China.;[Tan, Ying; Fang, Kai-Xin; Feng, Ying] Tsinghua Univ, Tsinghua Shenzhen Int Grad Sch, State Key Lab Chem Oncogen, Key Lab Chem Biol, Shenzhen, Peoples R China.;[Lu, Liang-Qiu] Chinese Acad Sci, Lanzhou Inst Chem Phys LICP, State Key Lab Oxo Synth & Select Oxidat, Lanzhou 730000, Peoples R China.;[Lu, Liang-Qiu] Henan Normal Univ, Sch Chem & Chem Engn, Xinxiang 453007, Henan, Peoples R China.
通讯机构:
[Prof. Ying Tan] S;[Prof. Liang-Qiu Lu] C;CCNU-uOttawa Joint Research Centre, Key Laboratory of Pesticide & Chemical Biology, Ministry of Education, College of Chemistry, Central China Normal University, 152 Luoyu Road, 430079 Wuhan, Hubei, P. R. China<&wdkj&>State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics (LICP), Chinese Academy of Sciences, 730000 Lanzhou, P. R. China<&wdkj&>School of Chemistry and Chemical Engineering, Henan Normal University, 453007 Xinxiang, Henan, China<&wdkj&>State Key Laboratory of Chemical Oncogenomics, Key Laboratory of Chemical Biology, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, P. R. China
关键词:
Antitumor Activity;Aza-Ortho-Quinone Methide;Aza-Sulfur Ylide;Azaheterocycle;Transition Metal Catalysis
摘要:
Metal-polarized aza-ortho-quinone methides (aza-o-QMs) are a unique and efficient handle for azaheterocycle synthesis. Despite great achievements, the potential of these reactive intermediates has not yet been fully exploited, especially the new reaction modes. Herein, we disclosed an unprecedented dearomatization process of metal-polarized aza-o-QMs, affording transient dearomatized spiroaziridine intermediates. Based on this serendipity, we accomplished three sequential dearomatization-rearomatization reactions of benzimidazolines with aza-sulfur ylides, enabling the divergent synthesis of bis-nitrogen heterocycles with high efficiency and flexibility. Moreover, experimental and theoretical studies were performed to explain the proposed mechanisms and observed selectivity. Further cellular evaluation of the dibenzodiazepine products identified a hit compound for new antitumor drugs.
作者机构:
[Zhang, Zhi-Han; Lu, Liang-Qiu; Yu, Xu-Hui; Xiao, Wen-Jing; Shi, De-Qing] Cent China Normal Univ, Coll Chem, Key Lab Pesticide & Chem Biol, Minist Educ, 152 Luoyu Rd, Wuhan 430079, Hubei, Peoples R China.;[Xiao, Wen-Jing] Shanghai Inst Organ Chem, State Key Lab Organometall Chem, 345 Lingling Rd, Shanghai 200032, Peoples R China.
通讯机构:
[De-Qing Shi] K;Key Laboratory of Pesticide & Chemical Biology, Ministry of Education, College of Chemistry, Central China Normal University, 152 Luoyu Road, Wuhan, Hubei 430079, China
摘要:
The asymmetric Michael addition of phosphorus nucleophiles to electron-deficient alkenes is one of the most direct and atom-economical methods to provide chiral organophosphorus compounds with high efficiency in recent years. Herein, we report a cobalt-catalyzed imidazolyl-directed asymmetric phospha-Michael-type reaction of diarylphosphine oxides with electron-deficient alkenes for synthesizing chiral organophosphorus compounds in moderate to good yields and good to excellent enantioselectivities (25 examples, up to 99% yield, and 99% ee). This protocol features broad substrate scope, good functional group tolerance, and mild conditions as well as avoids the release of massive metal wastes and the use of noble transition metal catalysts. The excellent enantioselectivity of the phospha-Michael reaction can be due to the adoption of a novel chiral N4-ligand. Furthermore, the DFT calculation indicates that the bulky 2,4,6-(i-Pr)3C6H2 group of the ligand induces large steric hindrance which blocks the nucleophilic attack from the Si-face.
作者机构:
[Lu, Liang-Qiu; Rao, Li; Zhou, Zheng-Xin; Xiao, Wen-Jing; Li, Yu-Jie; Liu, Xiao-Peng; Xiao, Yu-Qing] Cent China Normal Univ, CCNU uOttawa Joint Res Ctr, Key Lab Pesticide & Chem Biol, Minist Educ,Coll Chem, 152 Luoyu Rd, Wuhan 430079, Hubei, Peoples R China.;[Li, Miao-Miao] Zhengzhou Univ, Henan Inst Adv Technol, Div Mol Catalysis & Synth, Zhengzhou 45000, Peoples R China.;[Cao, Meng-Yue; Liu, Xiao-Peng] Westlake Univ, Sch Sci, Hangzhou 310024, Peoples R China.;[Lu, Liang-Qiu] Chinese Acad Sci, Lanzhou Inst Chem Phys LICP, State Key Lab Oxo Synth & Select Oxidat, Lanzhou 730000, Peoples R China.;[Lu, Liang-Qiu] Henan Normal Univ, Sch Chem & Chem Engn, Xinxiang 453007, Henan, Peoples R China.
通讯机构:
[Dr. Li Rao; Prof. Liang-Qiu Lu] C;CCNU-uOttawa Joint Research Centre, Key Laboratory of Pesticide & Chemical Biology, Ministry of Education, College of Chemistry, Central China Normal University, 152 Luoyu Road, Wuhan, Hubei, 430079 China<&wdkj&>State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics (LICP), Chinese Academy of Sciences, Lanzhou, 730000 P. R. China<&wdkj&>School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, Henan, 453007 China<&wdkj&>CCNU-uOttawa Joint Research Centre, Key Laboratory of Pesticide & Chemical Biology, Ministry of Education, College of Chemistry, Central China Normal University, 152 Luoyu Road, Wuhan, Hubei, 430079 China
摘要:
Ring-opening transformations of donor-acceptor (D-A) cyclopropanes enable the rapid assembly of complex molecules. However, the enantioselective formation of chiral quaternary stereocenters using substrates bearing two different acceptors remains a challenge. Herein, we describe the first palladium-catalyzed highly diastereo- and enantioselective (3+2) cycloaddition of vinyl cyclopropanes bearing two different electron-withdrawing groups, a subset of D-A cyclopropanes. The key to the success of this reaction is the remote stereoinduction through hydrogen bond from chiral ligands, which thereby addressed the aforementioned challenge. A variety of chiral five-membered heterocycles were produced in good yields and with high stereoselectivity (up to 99 % yields, 99 : 1 er and >19 : 1 dr). In-depth mechanistic investigations, including control experiments and theoretical calculations, revealed the origin of the stereoselectivity and the importance of H-bonding in stereocontrol.
作者机构:
[Cheng, Ying; Xiao, Wen-Jing; Chen, Jia-Rong; Shi, De-Qing; Li, Tian-Tian; Chen, JR] Cent China Normal Univ, Coll Chem, Engn Res Ctr Photoenergy Utilizat Pollut Control &, 152 Luoyu Rd, Wuhan 430079, Hubei, Peoples R China.;[Xiao, Wen-Jing] Shanghai Inst Organ Chem, State Key Lab Organometall Chem, 345 Lingling Rd, Shanghai 200032, Peoples R China.
通讯机构:
[Shi, DQ; Chen, JR ] C;Cent China Normal Univ, Coll Chem, Engn Res Ctr Photoenergy Utilizat Pollut Control &, 152 Luoyu Rd, Wuhan 430079, Hubei, Peoples R China.
摘要:
Radical Cross‐CouplingA copper‐catalyzed enantioselective three‐component radical relay 1,2‐alkylesterification of 1,3‐dienes using cycloalkyl hydroperoxides and carboxylic acids was reported. This protocol features broad substrate scope and good functional group tolerance with respect to each component, providing practical access to a variety of distally keto‐functionalized chiral allylic esters with high enantioselectivity under mild and redox‐neutral conditions. Abstract Transition‐metal‐catalyzed radical relay cross‐coupling reactions of 1,3‐dienes have recently emerged as one of the most powerful methods for construction of structurally diverse allylic compound in a single chemical step. However, there still has been limited success in expanding substrate scope of radical precursors and coupling partners, as well as exploring catalytic asymmetric variants. Herein, we report a copper‐catalyzed enantioselective three‐component 1,2‐alkylesterification of 1,3‐dienes using cycloalkyl hydroperoxides as the carbonyl‐containing alkyl radical sources and carboxylic acids as O‐nucleophiles under mild and redox‐neutral conditions. This protocol features broad substrate scope and good functional group tolerance with respect to each component, providing practical access to a variety of distally keto‐functionalized allylic esters with high enantioselectivity. Mechanistic studies suggest the involvement of a sequential radical relay and C−O cross‐coupling in this three‐component radical reaction.
摘要:
Radical single carbonylation reactions with CO constitute a direct and robust strategy toward various carbonyl compounds from readily available chemicals, and have been extensively studied over the past decades. However, realizing highly selective catalytic systems for controlled double radical carbonylation reactions has remained a substantial challenge, particularly for the more advanced multi‐component variants, despite their great potential value. Herein, we report a visible light‐driven radical relayed five‐component radical double aminocarbonylation reaction of unactivated alkenes using CO under metal‐free conditions. This protocol provides direct access to valuable γ‐trifluoromethyl α‐ketoamides with good yields and high selectivity. Crucial was the identification of distinct dual roles of amine coupling partners, sequentially acting as electron donors for the formation of photoactive electron donor‐acceptor (EDA) complexes with radical precursors and then as a CO acceptor via nitrogen radical cations to form carbamoyl radicals. Cross‐coupling of carbamoyl radicals with the acyl radicals that are formed in an alkene‐based relay process affords double aminocarbonylation products.
期刊:
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY,2023年145(22):12233-12243 ISSN:0002-7863
通讯作者:
Xiao, Wen-Jing;Chen, JR;Jiang, M;Xiao, WJ
作者机构:
[Qu, Wen-Yuan; Xiao, Wen-Jing; Chen, Jia-Rong; Zhou, Xue-Song; Liu, Xiao-Peng; Xiao, WJ; Zhang, Zhihan; Chen, JR] Cent China Normal Univ, Coll Chem, Wuhan 430079, Hubei, Peoples R China.;[Jiang, Min] Hangzhou Normal Univ, Coll Mat Chem & Chem Engn, Hangzhou 310036, Zhejiang, Peoples R China.;[Xiao, Wen-Jing; Chen, Jia-Rong; Xiao, WJ; Chen, JR] Wuhan Inst Photochem & Technol, Wuhan 430083, Hubei, Peoples R China.;[Xiao, Wen-Jing; Xiao, WJ] Shanghai Inst Organ Chem, State Key Lab Organometall Chem, Shanghai 200032, Peoples R China.;[Chen, Jia-Rong; Chen, JR] Henan Normal Univ, Sch Chem & Chem Engn, Xinxiang 453007, Peoples R China.
通讯机构:
[Jiang, M ] H;[Xiao, WJ ] S;[Xiao, WJ; Chen, JR ] C;Cent China Normal Univ, Coll Chem, Wuhan 430079, Hubei, Peoples R China.;Hangzhou Normal Univ, Coll Mat Chem & Chem Engn, Hangzhou 310036, Zhejiang, Peoples R China.
作者机构:
[Bao-Cheng Wang; Dr. Li Rao; Bao-Le Qu; Fen-Ya Xiong; Prof. Wen-Jing Xiao; Bao-Cheng Wang Bao-Cheng Wang Bao-Cheng Wang; Dr. Li Rao Dr. Li Rao Dr. Li Rao; Bao-Le Qu Bao-Le Qu Bao-Le Qu; Fen-Ya Xiong Fen-Ya Xiong Fen-Ya Xiong; Prof. Wen-Jing Xiao Prof. Wen-Jing Xiao Prof. Wen-Jing Xiao] CCNU-uOttawa Joint Research Centre, Key Laboratory of Pesticide & Chemical Biology, Ministry of Education, College of Chemistry, Central China Normal University, 152 Luoyu Road, 430079 Wuhan, Hubei, P. R. China;State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics (LICP), Chinese Academy of Sciences, 730000 Lanzhou, P. R. China;School of Chemistry and Chemical Engineering, Henan Normal University, 453007 Xinxiang, Henan, China;[Kai-Xin Fang; Ying Feng; Prof. Ying Tan; Kai-Xin Fang Kai-Xin Fang Kai-Xin Fang; Ying Feng Ying Feng Ying Feng; Prof. Ying Tan Prof. Ying Tan Prof. Ying Tan] State Key Laboratory of Chemical Oncogenomics, Key Laboratory of Chemical Biology, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, P. R. China;[Prof. Liang-Qiu Lu; Prof. Liang-Qiu Lu Prof. Liang-Qiu Lu Prof. Liang-Qiu Lu] CCNU-uOttawa Joint Research Centre, Key Laboratory of Pesticide & Chemical Biology, Ministry of Education, College of Chemistry, Central China Normal University, 152 Luoyu Road, 430079 Wuhan, Hubei, P. R. China<&wdkj&>State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics (LICP), Chinese Academy of Sciences, 730000 Lanzhou, P. R. China<&wdkj&>School of Chemistry and Chemical Engineering, Henan Normal University, 453007 Xinxiang, Henan, China
通讯机构:
[Prof. Ying Tan; Prof. Ying Tan Prof. Ying Tan Prof. Ying Tan] S;[Prof. Liang-Qiu Lu; Prof. Liang-Qiu Lu Prof. Liang-Qiu Lu Prof. Liang-Qiu Lu] C;CCNU-uOttawa Joint Research Centre, Key Laboratory of Pesticide & Chemical Biology, Ministry of Education, College of Chemistry, Central China Normal University, 152 Luoyu Road, 430079 Wuhan, Hubei, P. R. China<&wdkj&>State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics (LICP), Chinese Academy of Sciences, 730000 Lanzhou, P. R. China<&wdkj&>School of Chemistry and Chemical Engineering, Henan Normal University, 453007 Xinxiang, Henan, China<&wdkj&>State Key Laboratory of Chemical Oncogenomics, Key Laboratory of Chemical Biology, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, P. R. China
关键词:
Antitumor Activity;Aza-Ortho-Quinone Methide;Aza-Sulfur Ylide;Azaheterocycle;Transition Metal Catalysis
作者机构:
[Lu, Liang-Qiu; Lu, LQ; He, Lin; Qu, Bao-Le; Xiao, Wen-Jing; Shi, Jun-Wei; Shi, Bin] Cent China Normal Univ, Coll Chem, CCNU uOttawa Joint Res Ctr, Key Lab Pesticide & Chem Biol, Wuhan 430079, Hubei, Peoples R China.;[Lu, Liang-Qiu] Henan Normal Univ, Sch Chem & Chem Engn, Xinxiang 453007, Henan, Peoples R China.;[Lu, Liang-Qiu] Chinese Acad Sci, Lanzhou Inst Chem Phys LICP, State Key Lab Oxo Synth & Select Oxidat, Lanzhou 730000, Gansu, Peoples R China.
通讯机构:
[Lu, LQ ] C;Cent China Normal Univ, Coll Chem, CCNU uOttawa Joint Res Ctr, Key Lab Pesticide & Chem Biol, Wuhan 430079, Hubei, Peoples R China.
摘要:
Indoline skeletons are widely found in many natural isolates and pharmaceuticals, making indoline synthesis an ongoing research hotspot in synthetic chemistry. However, the catalytic asymmetric de novo construction of indolines bearing chiral quaternary stereocenters remains challenging. Herein, we present a solution to this unmet challenge through copper-catalyzed asymmetric [4 + 1] cycloadditions of ethynylbenzoxazinones with sulfur ylides, which are formed in situ by photoinduced carbene transfer. As a result, a wide range of chiral indolines bearing C2-quaternary stereocenters are obtained with good enantio- and diastereoselectivities (up to 19 : 1 dr and 96 : 4 er).
作者机构:
[Xiao, Wen-Jing; Chen, Jia-Rong; Wang, Peng-Zi] Cent China Normal Univ, Coll Chem, Key Lab Pesticides & Chem Biol, Minist Educ, Wuhan, Peoples R China.;[Chen, Jia-Rong] Henan Normal Univ, Sch Chem & Chem Engn, Xinxiang, Henan, Peoples R China.
通讯机构:
[Wen-Jing Xiao; Jia-Rong Chen] K;Key Laboratory of Pesticides & Chemical Biology Ministry of Education, College of Chemistry, Central China Normal University, Wuhan, China<&wdkj&>School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, China<&wdkj&>Key Laboratory of Pesticides & Chemical Biology Ministry of Education, College of Chemistry, Central China Normal University, Wuhan, China
摘要:
Creating, conserving and modifying the stereochemistry of organic compounds has been the subject of significant research efforts in synthetic chemistry. Most synthetic routes are designed according to the stereoselectivity-determining step. Stereochemical editing is an alternative strategy, wherein the chiral-defining or geometry-defining steps are independent of the construction of the major scaffold or complexity. It enables late-stage alterations of stereochemistry and can generate isomers from a single compound. However, in many instances, stereochemical editing processes are contra-thermodynamic, meaning the transformation is unfavourable. To overcome this barrier, photocatalysis uses photogenerated radical species and introduces thermochemical biases. A range of synthetically valuable contra-thermodynamic stereochemical editing processes have been invented, including deracemization of chiral molecules, positional alkene isomerization and dynamic epimerization of sugars and diols. In this Review, we highlight the fundamental mechanisms of visible-light photocatalysis and the general reactivity modes of the photogenerated radical intermediates towards contra-thermodynamic stereochemical editing processes. Stereochemical editing is a strategy to access three-dimensional skeletons, where the stereochemistry-defining steps are decoupled from the major connectivity-forming reactions. This Review highlights recent advances in the area of light-driven contra-thermodynamic stereochemical editing.