Article
Chemistry, Organic
Xue-Zu Deng, Zi-Yan Chen, Yang Song, Fei Xue, Motoki Yamane, Yan-Ni Yue
Summary: A new method using rhodium-catalyzed direct acylation has been developed for the construction of alpha,beta-unsaturated ketones, providing access to a variety of synthetically useful functionalities with high yields. Importantly, this method is also applicable for late-stage functionalization of pharmaceuticals with high yields.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Wen-Hui Bao, Xuesong Wu
Summary: A visible-light-driven deoxygenative cross-coupling reaction of alcohols with sulfonyl oxime ethers has been developed using xanthate salts as alcohol-activating reagents. By convenient generation and direct photoexcitation of xanthate anions, a broad range of alcohols, including primary ones, can efficiently undergo this transformation to yield diverse oxime ethers and derivatives. This one-pot protocol offers mild conditions, broad substrate scope, and late-stage applicability without the need for external photocatalysts or electron donor-acceptor complex formation.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Stefanie Mayr, Marta Marin-Luna, Hendrik Zipse
Summary: In Lewis base-mediated acylation reactions, secondary alcohols exhibit faster reaction rates compared to primary alcohols when reacting with benzoic anhydride derivatives, but this trend is inverted in reactions with sterically biased 1-naphthyl anhydrides. Increasing substrate size accelerates the acylation process, with a greater effect observed for secondary alcohols. Computational results suggest that acylation rates are influenced by noncovalent interactions, with stronger interactions formed with secondary alcohols than with primary alcohols.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Jacquin October, Katrin Koehnke, Nico Thanheuser, Andreas J. Vorholt, Walter Leitner
Summary: In this study, long-chain anhydrides were synthesized using a green-catalytic procedure. The carbonylation of alkenes with carboxylic acids was employed to achieve the synthesis. The importance of the phosphine ligand and acid promotor in catalysis was demonstrated.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Jihye Kim, Jieun Jang, Yoonho Lee, Kwangmin Shin
Summary: In this study, a nickel hydride-catalyzed hydroacylation of aryl alkenes using aroyl fluorides was reported. The reaction proceeds without the need for an exogenous ligand, and the synthetic utility of the method was demonstrated.
Article
Chemistry, Organic
Zhenkun Chen, Fengzhi Zhang
Summary: The Catellani reaction is a palladium-catalyzed hydrocarbon-activated multicomponent tandem reaction that involves an aryl halide, an electrophilic coupling reagent, and a terminating reagent. Norbornenes serve as co-catalysts and play critical roles in this reaction. After more than two decades of development, the Catellani reaction has become a unique method for the synthesis of poly-functionalized aromatics from easily accessible starting materials, with advantages of cross-coupling and adjacent metallization, as well as excellent reactivity and wide applicability. This manuscript reviews the important advances in Catellani reactions over the last four years, providing valuable insights for researchers in this prosperous research area.
Article
Chemistry, Multidisciplinary
Sichan Dong, Xinjun Luan
Summary: The Catellani reaction, discovered by Catellani in 1997 and further developed by Catellani, Lautens, and others, is a powerful strategy for the synthesis of polysubstituted arenes. This method allows for the simultaneous functionalization of both ortho- and ipso-positions of aryl halides with different electrophiles and terminating agents under the cooperative catalysis of palladium and norbornene. The review focuses on the significant progress in such transformations and categorizes typical Catellani reactions into five parts based on the functionalization modes of ortho-C-H bonds: alkylation, arylation, amination, acylation, or thiolation.
CHINESE JOURNAL OF CHEMISTRY
(2021)
Article
Chemistry, Organic
Xueyan Du, Xiaozhe Yang, Han Wang, Xinguang Li, Murong Wang, Xiang Li, Ye Tao, Yaxing Yang, Xinqiang Tan, Feng Ren, Ping-Xin Zhou, Yong-Min Liang
Summary: A palladium/norbornene-catalyzed ortho-amination/allylation reaction of aryl iodides was developed, which enabled the construction of ortho-aminated allylbenzene using N-benzoyloxyamine as the amination reagent and homoallyl alcohol as the allylation reagent. The reaction exhibited good functional group tolerance and a wide substrate scope.
ORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Organic
Zhicheng Bao, Chaoqiang Wu, Jianbo Wang
Summary: We report the use of 1,1-bis[(pinacolato)boryl]methane as a new terminating reagent for a three-component coupling reaction involving aryl iodide and various electrophiles. By using bromoacetic esters or O-benzoyl hydroxylamine as electrophiles with slightly modified reaction conditions, a series of ortho-disubstituted benzylboronates can be synthesized, allowing for variation in the ortho-substituent. The reaction exhibits good tolerance towards different functional groups, and the resulting benzyl boronate products can be easily converted into diverse synthetically useful compounds.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Stefanie Mayr, Hendrik Zipse
Summary: The relative rates of Lewis base-catalyzed acylation of aryl-substituted 1,2-diols with anhydrides of varying sizes have been determined. Depending on the anhydride reagent structure, the secondary hydroxyl group of the 1,2-diol reacts faster than the primary one. This preference is further enhanced in the second acylation step from monoesters to diesters through size and additional steric effects. The first acylation step is found to be up to 35 times faster than the second one for primary alcohols due to neighboring group effects.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Chemistry, Physical
Sangeth Jenthra, Totan Mondal, Gregor Kemper, Marcus Lantzius-Beninga, Markus Hoelscher, Walter Leitner
Summary: A highly chemo- and regioselective decarboxylative Heck-type coupling of carboxylic acids and terminal olefins was achieved using a catalytic system composed of Pd(OAc)(2) in the presence of phosphine-sulfonamido ligands. The bulky ligand L1 favored the formation of 1,1-disubstituted branched olefins with high selectivity, while the less bulky ligand L2 resulted in the formation of 1,2-disubstituted linear products in high yield. Detailed mechanistic investigation revealed that the aryl substituent at the sulfonamide group of ligand L1 favored 1,2-insertion, while the less bulky ligand L2 favored 2,1-insertion.
Article
Biochemistry & Molecular Biology
Yunyun Zheng, Jiuling Li, Kai Wei
Summary: An efficient, high-yielding, and scalable method for the regioselective 3-acylation of indoles with anhydrides promoted by boron trifluoride etherate under mild conditions was reported. This novel protocol provides a simple way to prepare 3-(benzofuran-2-yl) indole in three steps.
Article
Chemistry, Multidisciplinary
Vinayak Botla, Marco Fontana, Aleksandr Voronov, Raimondo Maggi, Elena Motti, Giovanni Maestri, Nicola Della Ca'
Summary: Despite the advances in carbon-halogen bond formation, the selective functionalization of iodoaryls is still challenging. In this study, a one-pot synthesis of ortho-iodobiaryls from aryl iodides and bromides is reported using palladium/norbornene catalysis. The Catellani reaction involves the cleavage of a C(sp(2))-I bond, ortho C-H activation, oxidative addition of an aryl bromide, and restoration of the C(sp(2))-I bond, leading to the formation of palladacycles. A variety of valuable o-iodobiaryls have been synthesized with good yields, and their derivatization is described. A DFT study provides insights into the mechanism of the key reductive elimination step.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Simon Eder, Bowen Ding, Daisy B. Thornton, Darlene Sammut, Andrew J. P. White, Felix Plasser, Ifan E. L. Stephens, Martin Heeney, Stefano Mezzavilla, Florian Glocklhofer
Summary: Aromatic carboxylic anhydrides are important building blocks in organic materials chemistry. This study presents a unique conjugated cyclophane with four anhydride groups, which can be easily functionalized and exhibits high porosity. The tetraimides and octacarboxylate derived from the cyclophane show excellent electrochemical properties. NMR and EPR measurements confirm their aromaticity. This novel building block holds great potential in the development of organic materials.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Physical
E. Larina, A. A. Kurokhtina, N. A. Lagoda, A. F. Schmidt
Summary: This paper presents the study results on changes in the composition of palladium complexes responsible for substrate activation in the Mizoroki-Heck reaction. The catalytic activity of palladium complexes was found to be influenced by the concentration ratio of a tertiary phosphine, alkali metal halide, and palladium catalyst precursor. Only phosphine-free palladium complexes containing halide anions in their coordination sphere played a decisive role in the formation of reaction products when threshold values of the concentration ratio between halide ions and the tertiary phosphine were achieved. The nature of the cation and anion of a halide salt added to the catalytic system was found to have a key effect on the differential selectivity of the formation of different products under noncompetitive conditions.
KINETICS AND CATALYSIS
(2022)
