Pub Date : 2025-02-28Epub Date: 2025-02-14DOI: 10.1021/acs.orglett.5c00121
Jason C Genova, David A Nicewicz
We describe an approach to form conformationally rigid atropisomers with a variety of nucleophiles not commonly applicable to transition-metal-catalyzed methods. The use of organic photoredox catalysis renders this method operationally simple, as direct substrate oxidation followed by nucleophilic attack may furnish the products via site-selective C-H functionalization in moderate to quantitative yields. Density functional theory (DFT) computations estimated the rotational barriers and half-lives of the products.
{"title":"Synthesis of Biaryl Atropisomers via Site-Selective C-H Functionalization.","authors":"Jason C Genova, David A Nicewicz","doi":"10.1021/acs.orglett.5c00121","DOIUrl":"10.1021/acs.orglett.5c00121","url":null,"abstract":"<p><p>We describe an approach to form conformationally rigid atropisomers with a variety of nucleophiles not commonly applicable to transition-metal-catalyzed methods. The use of organic photoredox catalysis renders this method operationally simple, as direct substrate oxidation followed by nucleophilic attack may furnish the products via site-selective C-H functionalization in moderate to quantitative yields. Density functional theory (DFT) computations estimated the rotational barriers and half-lives of the products.</p>","PeriodicalId":54,"journal":{"name":"Organic Letters","volume":" ","pages":"1889-1894"},"PeriodicalIF":4.9,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143416851","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Re-catalyzed highly regio- and stereoselective o-C(sp2)–H silylalkenylation of arenes is reported using a directing group approach under ligand-, additive-, and base-free conditions. A series of imine directing groups (DGs) have been exploited on aromatic aldehydes to overcome de novo synthesis. This unique protocol allows us to access o-C–H activation of various heterocyclic moieties, including N-aryl 2-pyridones and arylpyridines. Sequential difunctionalization experiments have been performed. A series of mechanistic experiments have been carried out to gain mechanistic insight.
{"title":"Rhenium-Catalyzed C(sp2)–H Silylalkenylation of Arenes: An Anti-Markovnikov Linchpin Strategy","authors":"Suman Bhowmick, Annapurna Awasthi, Khushboo Tiwari, Pushpendra Yadav, Dharmendra Kumar Tiwari","doi":"10.1021/acs.orglett.4c04228","DOIUrl":"https://doi.org/10.1021/acs.orglett.4c04228","url":null,"abstract":"Re-catalyzed highly regio- and stereoselective <i>o</i>-C(sp<sup>2</sup>)–H silylalkenylation of arenes is reported using a directing group approach under ligand-, additive-, and base-free conditions. A series of imine directing groups (DGs) have been exploited on aromatic aldehydes to overcome <i>de novo</i> synthesis. This unique protocol allows us to access <i>o</i>-C–H activation of various heterocyclic moieties, including <i>N</i>-aryl 2-pyridones and arylpyridines. Sequential difunctionalization experiments have been performed. A series of mechanistic experiments have been carried out to gain mechanistic insight.","PeriodicalId":54,"journal":{"name":"Organic Letters","volume":"72 1","pages":""},"PeriodicalIF":5.2,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143526112","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Currently, the scope of the Nozaki-Hiyama-Kishi (NHK) reaction is limited to aldehydes and ketones to construct alcohol derivatives. Herein, we have described a visible-light-induced synergistic W/Cr(III)-catalyzed NHK-type gem-difluoroallylation reaction of unactivated cyclic and linear alkanes. The reaction merits feedstock materials, mild reaction conditions, and a wide functionality tolerance. Mechanistic studies imply the favorable reduction of CrCl3 to CrCl2 by reduced decatungstate W10O325-, thus closing the catalytic cycle.
{"title":"Visible-Light-Induced Synergistic W/Cr Catalyzed <i>gem</i>-Difluoroallylation of Unactivated Alkanes.","authors":"Zhijie Zhang, Yue Zhang, Xinyu Xie, Hua-Wei Liu, Tianshuai Zhu, Jing-Jing Zhang, Meng-Yang Hu, Zhen Chen","doi":"10.1021/acs.orglett.5c00464","DOIUrl":"10.1021/acs.orglett.5c00464","url":null,"abstract":"<p><p>Currently, the scope of the Nozaki-Hiyama-Kishi (NHK) reaction is limited to aldehydes and ketones to construct alcohol derivatives. Herein, we have described a visible-light-induced synergistic W/Cr(III)-catalyzed NHK-type <i>gem</i>-difluoroallylation reaction of unactivated cyclic and linear alkanes. The reaction merits feedstock materials, mild reaction conditions, and a wide functionality tolerance. Mechanistic studies imply the favorable reduction of CrCl<sub>3</sub> to CrCl<sub>2</sub> by reduced decatungstate W<sub>10</sub>O<sub>32</sub><sup>5-</sup>, thus closing the catalytic cycle.</p>","PeriodicalId":54,"journal":{"name":"Organic Letters","volume":" ","pages":"2016-2021"},"PeriodicalIF":4.9,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143447454","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Herein, we report a novel squaramide containing chiral bifunctional N-heterocyclic carbene (NHC) and its utilization in developing asymmetric intramolecular conjugate addition involving noncovalent interaction. Via concomitant activation of both electrophilic and nucleophilic centers of substrates, the reaction proceeds through a well-organized transition state, thereby affording products with up to 94% ee and a broad scope. The process is found to be scalable. The initial mechanistic study supports the bifunctional nature of the newly designed NHC.
{"title":"Bifunctional NHC-Catalyzed Asymmetric Intramolecular Conjugate Addition via Noncovalent Interaction","authors":"Ujjwal Maji, Arpita Baidya, Supriyo Das, Joyram Guin","doi":"10.1021/acs.orglett.5c00315","DOIUrl":"https://doi.org/10.1021/acs.orglett.5c00315","url":null,"abstract":"Herein, we report a novel squaramide containing chiral bifunctional N-heterocyclic carbene (NHC) and its utilization in developing asymmetric intramolecular conjugate addition involving noncovalent interaction. Via concomitant activation of both electrophilic and nucleophilic centers of substrates, the reaction proceeds through a well-organized transition state, thereby affording products with up to 94% ee and a broad scope. The process is found to be scalable. The initial mechanistic study supports the bifunctional nature of the newly designed NHC.","PeriodicalId":54,"journal":{"name":"Organic Letters","volume":"8 1","pages":""},"PeriodicalIF":5.2,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143526115","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-28DOI: 10.1021/acs.orglett.5c00604
Long Meng, Jia-Yi Pei, Jin-Bao Qiao, Yu-Ming Zhao
Building on our prior synthesis of the representative Ryanodane diterpene garajonone, we report here the chemical synthesis of anhydroryanodol, a significant degradation product of Ryanodane diterpenes that features distinct oxidation sites, utilizing the same advanced intermediate. This was accomplished through a series of late-stage regio- and stereoselective redox operations. This study, in conjunction with our earlier synthesis of garajonone, represents the first unified approach to the synthesis of Ryanodane diterpenes with differing oxidation sites based on a single synthetic strategy.
{"title":"Total Synthesis of Anhydroryanodol and Formal Synthesis of Ryanodol and Ryanodine","authors":"Long Meng, Jia-Yi Pei, Jin-Bao Qiao, Yu-Ming Zhao","doi":"10.1021/acs.orglett.5c00604","DOIUrl":"https://doi.org/10.1021/acs.orglett.5c00604","url":null,"abstract":"Building on our prior synthesis of the representative Ryanodane diterpene garajonone, we report here the chemical synthesis of anhydroryanodol, a significant degradation product of Ryanodane diterpenes that features distinct oxidation sites, utilizing the same advanced intermediate. This was accomplished through a series of late-stage regio- and stereoselective redox operations. This study, in conjunction with our earlier synthesis of garajonone, represents the first unified approach to the synthesis of Ryanodane diterpenes with differing oxidation sites based on a single synthetic strategy.","PeriodicalId":54,"journal":{"name":"Organic Letters","volume":"30 1","pages":""},"PeriodicalIF":5.2,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143526116","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-28Epub Date: 2025-02-19DOI: 10.1021/acs.orglett.5c00068
Debashis Barik, Rai-Shung Liu
Two distinct coupling reactions of α-aryldiazo ketones with vinyldiazo esters are described using gold catalyst (5 mol %) and Bu4NF promoter (1.5 equiv), respectively. This new synthetic scheme involves a prior rearrangement of α-aryldiazo ketones to generate diarylketenes under thermal conditions whereas vinyldiazo esters serve as nucleophiles to afford isolable 4-siloxy-1-diazo-pent-4-en-2-ones. This diazo-diazo cross-coupling reaction yields highly substituted cyclopentenones using gold catalyst and substituted pyrazole derivatives with Bu4NF promoter.
{"title":"Two Distinct Diazo-Diazo Cross-Coupling Reactions between α-Aryldiazo Ketones and Vinyldiazo Esters Using Gold Catalyst and Tetrabutylammonium Fluoride.","authors":"Debashis Barik, Rai-Shung Liu","doi":"10.1021/acs.orglett.5c00068","DOIUrl":"10.1021/acs.orglett.5c00068","url":null,"abstract":"<p><p>Two distinct coupling reactions of α-aryldiazo ketones with vinyldiazo esters are described using gold catalyst (5 mol %) and Bu<sub>4</sub>NF promoter (1.5 equiv), respectively. This new synthetic scheme involves a prior rearrangement of α-aryldiazo ketones to generate diarylketenes under thermal conditions whereas vinyldiazo esters serve as nucleophiles to afford isolable 4-siloxy-1-diazo-pent-4-en-2-ones. This diazo-diazo cross-coupling reaction yields highly substituted cyclopentenones using gold catalyst and substituted pyrazole derivatives with Bu<sub>4</sub>NF promoter.</p>","PeriodicalId":54,"journal":{"name":"Organic Letters","volume":" ","pages":"1871-1877"},"PeriodicalIF":4.9,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11877532/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143456287","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-28Epub Date: 2025-02-14DOI: 10.1021/acs.orglett.5c00287
Yuki Tateishi, Shota Nagasawa, Yoshiharu Iwabuchi
Herein, we report a novel photocatalytic tandem Ueno-Stork cyclization/intermolecular Giese addition sequence for the stereoselective difunctionalization of allylic alcohols. This reaction avoids the use of toxic reagents and complicated protocols typically required under classical Ueno-Stork conditions. Furthermore, the reaction system demonstrated good stereoselectivity with both cyclic and linear allylic alcohols.
{"title":"Photocatalytic Tandem Ueno-Stork Cyclization/Intermolecular Giese Addition Sequence for Stereoselective Difunctionalization of Allylic Alcohols.","authors":"Yuki Tateishi, Shota Nagasawa, Yoshiharu Iwabuchi","doi":"10.1021/acs.orglett.5c00287","DOIUrl":"10.1021/acs.orglett.5c00287","url":null,"abstract":"<p><p>Herein, we report a novel photocatalytic tandem Ueno-Stork cyclization/intermolecular Giese addition sequence for the stereoselective difunctionalization of allylic alcohols. This reaction avoids the use of toxic reagents and complicated protocols typically required under classical Ueno-Stork conditions. Furthermore, the reaction system demonstrated good stereoselectivity with both cyclic and linear allylic alcohols.</p>","PeriodicalId":54,"journal":{"name":"Organic Letters","volume":" ","pages":"1984-1988"},"PeriodicalIF":4.9,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11877517/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143416844","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-28DOI: 10.1021/acs.orglett.5c00257
Shoule Cai, Hongchi Liu, Yinjun Xie, Hanmin Huang
Great efforts have been devoted to synthesizing dithioethers due to their unique pharmaceutical properties. While significant success has been achieved in the synthesis of 1,1-dithioethers and 1,2-dithioethers, a concise and efficient strategy for the direct construction of 1,3-dithioethers has not yet been established. Herein, we developed a palladium-catalyzed thiomethylthiolation of allenes with dithioacetals to access a wide range of 1,3-dithioethers through the simultaneous construction of one carbon–carbon bond and one carbon–sulfur bond. A dithioacetal-coordinated cationic palladium complex was isolated and characterized, which was considered the crucial intermediate for this palladium-catalyzed transformation.
{"title":"Palladium-Catalyzed Insertion of Allenes into Dithioacetals To Access 1,3-Dithioethers","authors":"Shoule Cai, Hongchi Liu, Yinjun Xie, Hanmin Huang","doi":"10.1021/acs.orglett.5c00257","DOIUrl":"https://doi.org/10.1021/acs.orglett.5c00257","url":null,"abstract":"Great efforts have been devoted to synthesizing dithioethers due to their unique pharmaceutical properties. While significant success has been achieved in the synthesis of 1,1-dithioethers and 1,2-dithioethers, a concise and efficient strategy for the direct construction of 1,3-dithioethers has not yet been established. Herein, we developed a palladium-catalyzed thiomethylthiolation of allenes with dithioacetals to access a wide range of 1,3-dithioethers through the simultaneous construction of one carbon–carbon bond and one carbon–sulfur bond. A dithioacetal-coordinated cationic palladium complex was isolated and characterized, which was considered the crucial intermediate for this palladium-catalyzed transformation.","PeriodicalId":54,"journal":{"name":"Organic Letters","volume":"66 1","pages":""},"PeriodicalIF":5.2,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143518300","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-28DOI: 10.1021/acs.orglett.5c00581
Xiaofei Chen, Yihan Gao, Shuyu Yu, Jingyi Liang, Lei Zhou
An FeCl3-catalyzed [4 + 2] cycloaddition of vinyldiazo compounds with N-acyliminium cations generated from 3-hydroxyisoindolinones is described. A series of diazo-containing isoindolo[2,1-a]quinolinones were constructed in good yields with excellent diastereoselectivities, including those with three contiguous stereogenic centers. The resultant products were readily converted into various isoindolo[2,1-a]quinolinone derivatives based on the rich chemistry of the remaining diazo functionality.
{"title":"Lewis-Acid-Catalyzed Diastereoselective [4 + 2] Cycloaddition of Vinyldiazo Compounds with N-Acyliminium Cations","authors":"Xiaofei Chen, Yihan Gao, Shuyu Yu, Jingyi Liang, Lei Zhou","doi":"10.1021/acs.orglett.5c00581","DOIUrl":"https://doi.org/10.1021/acs.orglett.5c00581","url":null,"abstract":"An FeCl<sub>3</sub>-catalyzed [4 + 2] cycloaddition of vinyldiazo compounds with <i>N</i>-acyliminium cations generated from 3-hydroxyisoindolinones is described. A series of diazo-containing isoindolo[2,1-<i>a</i>]quinolinones were constructed in good yields with excellent diastereoselectivities, including those with three contiguous stereogenic centers. The resultant products were readily converted into various isoindolo[2,1-<i>a</i>]quinolinone derivatives based on the rich chemistry of the remaining diazo functionality.","PeriodicalId":54,"journal":{"name":"Organic Letters","volume":"52 1","pages":""},"PeriodicalIF":5.2,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143518303","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Heteroatomic groups in alkenes typically direct thermodynamically favored chain walking of C═C bonds toward themselves, thereby facilitating C-H bond functionalization near the heteroatoms. We present herein an efficient cobalt-catalyzed contra-thermodynamic remote hydroboration of alkenylboronates with pinacolborane to synthesize chiral 1,n-diboronates. This protocol features a broad substrate scope, high functional group tolerance, and excellent enantioselectivity. Mechanistic studies indicate the involvement of a chain-walking process. Gram-scale reactions and various product derivatizations further highlight its practicality.
{"title":"Enantioselective Cobalt-Catalyzed Remote Hydroboration of Alkenylboronates.","authors":"Wenke Dong, Zheming Liu, Anbang Bai, Xiaoyu Zhang, Peiwen Han, Jingyi He, Chenchen Li","doi":"10.1021/acs.orglett.5c00107","DOIUrl":"10.1021/acs.orglett.5c00107","url":null,"abstract":"<p><p>Heteroatomic groups in alkenes typically direct thermodynamically favored chain walking of C═C bonds toward themselves, thereby facilitating C-H bond functionalization near the heteroatoms. We present herein an efficient cobalt-catalyzed contra-thermodynamic remote hydroboration of alkenylboronates with pinacolborane to synthesize chiral 1,<i>n</i>-diboronates. This protocol features a broad substrate scope, high functional group tolerance, and excellent enantioselectivity. Mechanistic studies indicate the involvement of a chain-walking process. Gram-scale reactions and various product derivatizations further highlight its practicality.</p>","PeriodicalId":54,"journal":{"name":"Organic Letters","volume":" ","pages":"1895-1900"},"PeriodicalIF":4.9,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143412399","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
扫码关注我们
求助内容：
应助结果提醒方式：
京公网安备 11010802042870号