Article
Chemistry, Physical
Aoife M. Buckley, Daniel C. Crowley, Thomas A. Brouder, Alan Ford, U. B. Rao Khandavilli, Simon E. Lawrence, Anita R. Maguire
Summary: A new class of dirhodium carboxylate catalysts, derived from specific 2-fenchyloxy or 2-menthyloxy arylacetic acids, have shown excellent enantioselectivity and trans diastereoselectivity across a range of transformations. These catalysts are highly efficient in various reactions, such as C-H insertion, intramolecular aromatic addition, and oxonium ylide formation and rearrangement, displaying up to 93% ee in product yield.
Article
Chemistry, Organic
Julia O. Strelnikova, Nikolai Rostovskii, Olesya Khoroshilova, Alexander F. Khlebnikov, Mikhail S. Novikov
Summary: A high-yielding method for synthesizing 2H-1,3,5-oxadiazines by the rhodium(II)- or copper(II)-catalyzed reaction of 1,2,4-oxadiazoles with alpha-diazo esters has been developed, where the N2-attack and N4-attack of the carbenoid cause different oxadiazole ring openings controlled by the substitution at C5.
SYNTHESIS-STUTTGART
(2021)
Article
Chemistry, Organic
Joanna C. Lee, James D. Cuthbertson, Nicholas J. Mitchell
Summary: We report the photocatalytic C2-alkylation of tryptophan using bromodifluoroacetate/acetamide-derived radical precursors. This reaction is rapid, additive-free, operationally simple, and tolerates diverse functionality. It enables late-stage modification of a variety of complex peptides, including examples of biological significance.
Article
Chemistry, Organic
Yan Zhu, Ying Shao, Shengbiao Tang, Jiangtao Sun
Summary: A novel dearomative 1,4-rearrangement reaction of 2-carbonateindoles with aryl diazoacetates has been developed in the presence of a copper catalyst, leading to the formation of rearrangement products with an all-carbon quaternary center and two newly formed C-C bonds. This reaction involves the disruption of indole aromaticity and 1,4-carboxylate rearrangements.
ORGANIC CHEMISTRY FRONTIERS
(2022)
Article
Chemistry, Applied
Hisanori Nambu, Ryoya Amano, Takafumi Tamura, Takayuki Yakura
Summary: This study describes the dirhodium(II)-catalyzed intramolecular insertion of aryldiazoacetates into unactivated primary C-H bonds. The reaction shows high selectivity and provides a direct route to 2-unsubstituted indane-1-carboxylates and specific isomers with ortho-substituted groups. Furthermore, a chemoselective C-H insertion reaction of aryldiazoacetate with a 1-oxyethyl substituent is achieved using a specific protecting group.
ADVANCED SYNTHESIS & CATALYSIS
(2022)
Article
Chemistry, Multidisciplinary
Reyner D. Vargas, Yuxuan Ding, Hallie O. Trial, Rouyu Qian, Zachary T. Ball
Summary: This study explores a catalytic proximity-induced methodology for covalent modification of glycopeptides using boronic acids as a saccharide recognition element, providing a new approach for saccharide recognition.
CHEMICAL COMMUNICATIONS
(2023)
Article
Biochemistry & Molecular Biology
Yulia A. Antonova, Yulia V. Nelyubina, Sema L. Ioffe, Andrey A. Tabolin
Summary: A Rh(II)-catalyzed reaction of cyclic nitronates with vinyl diazoacetates proceeds as an annulation reaction, producing bicyclic unsaturated nitroso acetals. Optimization of reaction conditions revealed the use of Rh(II) octanoate as the preferred catalyst in THF at room temperature, allowing the preparation of target products in good yields and excellent diastereoselectivity. Under basic conditions, these nitroso acetals undergo ring contraction into the corresponding pyrroles, and both transformations can be performed in a one-pot fashion.
Article
Chemistry, Organic
Miriam Ruiz-Serrano, Pilar Lopez-Alvarado, J. Carlos Menendez
Summary: Researchers found that the reaction between an a-formylcyclohexanone derivative and tosyl azide, in the presence of rhodium trifluoroacetate dimer, produced an acylsulfonamide derivative. This transformation is proposed to occur through a domino mechanism involving the in situ generation of an a-diazoketone, which is then transformed into a rhodium carbenoid and combined with N-tosylformamide, a side product of the first step. Overall, this transformation results in the formation of a C-N bond between the formyl carbon and the azide nitrogen adjacent to the sulfonyl group.
Review
Chemistry, Multidisciplinary
Santosh Kumar Sahu, Pradyota Kumar Behera, Prabhupada Choudhury, Madhusudan Sethi, Satyaban Jena, Laxmidhar Rout
Summary: This study summarizes the stereochemical outcomes of [3+2] cycloaddition using rhodium carbene-mediated diazo decomposition for highly diastereoselective poly oxacarbocycles formation. Further exploration with other transition metals and ylides is needed for synthesis of bridged polyheterocycles with potential drug candidate structures similar to known compounds like anthecularin, artemisinin, englerin and intracarene. This review presents a future outlook for organic chemists to explore the synthesis of bridged polyheterocarbocycles.
NEW JOURNAL OF CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Weiyu Li, Sen Li, Claire Empel, Rene M. Koenigs, Lei Zhou
Summary: This study describes a photocatalytic self-(3+2) cycloaddition of vinyldiazo compounds for the synthesis of cyclopentene derivatives with conservation of one diazo functional group. Experimental and density functional theory investigations reveal that the reaction is initiated by an unusual single electron oxidation of the vinyldiazo compounds, without involvement of photolysis for the generation of free carbene species. The synthetic applications of the resulting cyclopentenyl a-diazo compounds are demonstrated based on the versatile chemistry of the diazo functional group.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Chuan Wan, Yuena Wang, Chenshan Lian, Qi Chang, Yuhao An, Jiean Chen, Jinming Sun, Zhanfeng Hou, Dongyan Yang, Xiaochun Guo, Feng Yin, Rui Wang, Zigang Li
Summary: This study develops a novel visible-light-driven thioacetal activation reaction for facile modification of histidine residues. The method allows chemo-selective modification on peptides and proteins, enabling efficient histidine-proteome profiling. 78 histidine containing proteins were found for the first time, most of which function in metal accumulation in brain related diseases.
Article
Chemistry, Multidisciplinary
Takanobu Saito, Joaquim Caner, Naoyuki Toriumi, Nobuharu Iwasawa
Summary: A novel method for the meta-selective C-H carboxylation of 1,1-diarylethylene derivatives using a rhodium catalyst and a stoichiometric reductant has been achieved. The introduction of a carboxyl group to the aryl ring at the meta-position was enabled with high selectivity. Both experimental and computational mechanistic studies indicate that a specific rhodium migration process plays a key role in this unusual aryl-to-aryl 1,2-rhodium shift.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Organic
Yu-Ting Tian, Fa-Guang Zhang, Jun-An Ma
Summary: A regioselective [3 + 2] cyclo-addition reaction of 3-alkynoates with Seyferth-Gilbert reagent was developed with the trigger of Et3N to produce a series of trisubstituted pyrazole-3-phosphonates. A one-pot cycloaddition/alkylation sequence was further utilized to access the fully substituted pyrazoles.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Vaishnavi N. Nair, Volga Kojasoy, Croix J. Laconsay, Wang Yeuk Kong, Dean J. Tantillo, Uttam K. Tambar
Summary: The study developed catalyst-controlled regiodivergent rearrangements of onium-ylides derived from indole substrates, with experimental and computational studies revealing different mechanistic pathways. The methodology was successfully applied in the total synthesis of the natural product and further functional group transformations.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Chemistry, Multidisciplinary
Ken-Loon Choo, Bijan Mirabi, Karl Z. Demmans, Mark Lautens
Summary: Enantioenriched spiro-oxiranes with three contiguous stereocenters were synthesized using a rhodium-catalyzed cascade reaction, enabling the formation of a spirocyclic framework in a single step. Both sp(2)- and sp-hybridized carbon nucleophiles were found to be efficient initiators, yielding products with different functional groups. Derivatization studies demonstrated the synthetic versatility of the products' epoxide and alkyne moieties. DFT calculations were employed to explain spectroscopic discrepancies between solution- and solid-state structures of the products.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Multidisciplinary
Ryan C. Cammarota, Wenbin Liu, John Bacsa, Huw M. L. Davies, Matthew S. Sigman
Summary: Leveraging congested catalyst scaffolds is a key strategy for altering substrate site-selectivity in C-H functionalization reactions. In this study, a new set of descriptors (SMART) was developed to quantify reactive site spatial constraints for a library of dirhodium catalysts and predict site-selectivity for C-H functionalization reactions. The study also developed global site-selectivity models to assess the roles of steric congestion and dirhodium-carbene electrophilicity in controlling the site of C-H functionalization.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Editorial Material
Gastroenterology & Hepatology
John P. Haydek, Frank I. Scott
Summary: This article is related to the papers by Rosiou et al.
ALIMENTARY PHARMACOLOGY & THERAPEUTICS
(2022)
Article
Chemistry, Organic
Robert W. Kubiak, William F. Tracy, Joshua S. Alford, Huw M. L. Davies
Summary: This paper describes a rhodium-catalyzed enantioselective synthesis of 1-phenoxy-cyclopropane-1-carbaldehydes by intermolecular cyclopropanation of terminal alkenes followed by imine hydrolysis. The reaction proceeds via rhodium-stabilized donor/acceptor carbene intermediates, and the study demonstrates compatibility of a heteroatom donor group with enantioselective transformation.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Yannick T. Boni, Ryan C. Cammarota, Kuangbiao Liao, Matthew S. Sigman, Huw M. L. Davies
Summary: In this work, C-H functionalization of silyl ethers via carbene-induced C-H insertion has been achieved, providing an efficient synthetic disconnection strategy. The use of different catalyst preferences has enabled site- and stereoselective functionalization at different positions relative to the siloxy group. Additionally, a machine learning model has been developed to predict the major product, aiding in the application of these methods to new substrates.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Physical
Jack C. Sharland, David Dunstan, Dyuti Majumdar, Jinhai Gao, Kian Tan, Hasnain A. Malik, Huw M. L. Davies
Summary: In the presence of HFIP, nucleophilic and reactive reagents are prevented from interacting with a rhodium carbene, allowing for efficient asymmetric cyclopropanation with high yield and stereoselectivity on a variety of compounds. A high-throughput screen was conducted to expand the scope of the reaction and develop complementary catalytic systems, leading to the enantioselective functionalization of complex molecules including API and natural products.
Article
Chemistry, Organic
Christian J. Bettencourt, Tanja Krainz, Sharon Chow, Brendan T. Parr, William F. Tracy, Paul V. Bernhardt, Huw M. L. Davies, Craig M. Williams
Summary: The rhodium(II)-catalyzed reaction of a model alkenyl donor/ acceptor N-sulfonyltriazole with a wide selection of furans has been reported. A range of structurally diverse carbocyclic and ring-opened products were obtained, in good to excellent yields, via selective cyclopropanation or zwitterionic rearrangement pathways, depending on the structural and electronic features of the furan substrate.
Article
Chemistry, Organic
Yannick T. Boni, Janakiram Vaitla, Huw M. L. Davies
Summary: Rhodium(II) catalyst-controlled site- and stereo-selective carbene insertion into the allylic C(sp3)-H bond of allyl boronates is achieved. The chiral catalyst Rh2(S-TPPTTL)4 exhibits high fidelity and asymmetric induction, enabling diastereoselective and enantioselective C-C bond formation without interference from the allyl boronate functionality. The resulting functionalized allyl boronates are amenable to stereo-selective allylations, leading to products with control of stereochemistry at four contiguous stereogenic centers.
Article
Chemistry, Physical
Korkit Korvorapun, Yannick T. Boni, Thomas C. Maier, Armin Bauer, Thomas Licher, John E. Macor, Volker Derdau, Huw M. L. Davies
Summary: Rhodium-catalyzed C-H insertion by donor/acceptor carbenes is a useful transformation in organic synthesis, but the site-selectivity of the C-H transformation on the target molecule is often a major issue. Chiral rhodium carbene intermediates can achieve site-selective C-H functionalizations of challenging substrates such as N-aryl and N-heteroaryl piperidines, leading to the formation of highly stereoselective C-2 products. Additionally, N-aryl morpholines and piperazines can selectively react at the alpha position to the N-aryl group.
Article
Chemistry, Organic
Farzaneh Saeedifard, Yasir Naeem, Yannick T. Boni, Yi-Chien Chang, Junxiang Zhang, Yadong Zhang, Bernard Kippelen, Stephen Barlow, Huw M. L. Davies, Seth R. Marder
Summary: Hole-transport materials based on triarylamine derivatives have critical applications in organic electronics. This study demonstrates a method using Rh-carbenoid chemistry to incorporate carboxylic esters and norbornene functional groups into triarylamine materials. The resulting materials exhibit similar properties to those synthesized by conventional means and offer the potential for diverse hole-transport materials with different functional groups.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Sebastian Fischer, Terrence-Thang H. Nguyen, Andreas Ratzenboeck, Huw M. L. Davies, Oliver Reiser
Summary: A stereoselective, solvent- and metal-free method for endocyclic C-C bond cleavage of monocyclopropanated cyclopentadienes mediated by strong acids has been developed. It leads to the formation of highly functionalized six-membered carbocycles with high stereocontrol. The critical step involves the formation of a cyclopropyl carbocation that undergoes endocyclic ring opening through an SN2'-type attack of various nucleophiles. Subsequent synthetic transformations demonstrate the versatility of the resulting cyclohexenes for the synthesis of compounds with nonconventional substitution patterns.
Article
Chemistry, Organic
Ziyi Chen, Qinyan Cai, Yannick T. Boni, Wenbin Liu, Jiantao Fu, Huw M. L. Davies
Summary: The rhodium-catalyzed enantioselective C-H functionalization of unactivated C-H bonds by donor/acceptor carbene-induced C-H insertion can be extended to substrates containing nitrogen functionality. The rhodium-stabilized donor/acceptor carbenes are generated by rhodium-catalyzed decomposition of aryldiazoacetates. The phthalimido group is the optimal nitrogen protecting group. C-H functionalization at the most sterically accessible site can be achieved using Rh-2(S-2-Cl-5-BrTPCP)(4) as catalyst, while Rh-2(S-TPPTTL)(4) is the most effective catalyst for functionalization at tertiary C-H bonds and for the desymmetrization of N-phthalimidocyclohexane.
Article
Chemistry, Organic
Maizie Lee, Huw M. L. Davies
Summary: The rhodium-catalyzed C-H functionalization of cyclohexadiene derivatives with diaryldiazomethanes, followed by oxidation with DDQ, allows for the synthesis of triarylmethanes. Two chiral dirhodium tetracarboxylates, Rh-2(S-PTAD)(4) and Rh-2(S-TPPTTL)(4), were identified as the optimal chiral catalysts for this transformation. This method demonstrates the ability of diaryldiazomethanes to perform intermolecular C-H insertion with high enantioselectivity and good yields. The broad substrate scope includes various aryl and heteroaryl substituents, including benzofuran and pyridine heterocycles.
Correction
Chemistry, Organic
Sebastian Fischer, Terrence-Thang H. Nguyen, Andreas Ratzenboeck, Huw M. L. Davies, Oliver Reiser
Article
Chemistry, Inorganic & Nuclear
Joshua K. Sailer, Jack C. Sharland, John Bacsa, Caleb F. Harris, John F. Berry, Djamaladdin G. Musaev, Huw M. L. Davies
Summary: A series of chiral bowl-shaped diruthenium(II,III) tetracarboxylate catalysts were prepared for asymmetric cyclopropanation reactions. These diruthenium catalysts self-assembled to form C(4)-symmetric bowl-shaped structures, similar to their dirhodium counterparts. The best catalyst, Ru-2(S-TPPTTL)(4)& BULL;BArF, achieved up to 94% ee in the cyclopropanation of various substrates. In contrast, the copper and cobalt congeners produced catalysts with little to no asymmetric induction. Computational studies revealed that the carbene complexes of the dicopper and dicobalt systems were prone to losing carboxylate ligands, which are essential for the bowl-shaped structure critical for asymmetric induction.
Article
Chemistry, Organic
Farzaneh Saeedifard, Yasir Naeem, Yannick T. Boni, Yi-Chien Chang, Junxiang Zhang, Yadong Zhang, Bernard Kippelen, Stephen Barlow, Huw M. L. Davies, Seth R. Marder
Summary: Hole-transport materials (HTMs) based on triarylamine derivatives are important in organic electronic applications. This study presents a method to incorporate carboxylic esters and norbornene functional groups into sp2 C-H bonds of triarylamine materials using Rh-carbenoid chemistry. The resulting materials exhibit similar properties to those synthesized by conventional means and offer a straightforward approach to diverse HTMs with different functional groups.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
