Article
Chemistry, Physical
Somayyeh Gandomkar, Raquel Rocha, Frieda A. Sorgenfrei, Lia Martinez Montero, Michael Fuchs, Wolfgang Kroutil
Summary: The study implemented an oxidation step relying on a single PQQ-dependent dehydrogenase to achieve oxidation of both enantiomers. The stereoselective amination of the alpha,beta-unsaturated ketone intermediate was achieved using transaminases, and enantio-convergent amination of the racemic allylic alcohols was successfully completed in a sequential cascade.
Article
Chemistry, Multidisciplinary
Shang Gao, Jiaming Liu, Ming Chen
Summary: The study successfully synthesized compounds with high optical purity through catalytic asymmetric reactions, including (Z)-delta-hydroxymethyl-anti-homoallylic alcohols and alpha,beta-unsaturated aldehydes. Enantioconvergent pathways were utilized to achieve excellent optical purity.
Article
Chemistry, Multidisciplinary
Laura Edit Barabas, Diana Maria Scrob, Andrea Varga, Lorand Kiss, Monica Ioana Tosa, Csaba Paizs
Summary: This study developed a bi-enzymatic transaminase cascade using Pseudomonas psychrotolerans (PpS-TA) and human carbonic anhydrase II (hCAII) for efficient conversion of various (+/-)-1-phenylethan-1-amines to enantiopure (R)-amines and (S)-1-phenylethan-1-ols. The reaction medium, HEPES-DMSO, and a DMSO content of 30% were found to be suitable, improving solubilization of substrates and allowing for complete reduction of acetophenone. The cellular cascade showed improved viability compared to soluble enzymes, allowing for gram-scale conversion of (+/-)-1-phenylethan-1-amine to enantiopure products in high yields.
REACTION CHEMISTRY & ENGINEERING
(2023)
Article
Chemistry, Organic
Jiantao Fu, Zoe Vaughn, Andrew F. Nolting, Qi Gao, Dexi Yang, Christopher H. Schuster, Dipannita Kalyani
Summary: This manuscript presents the development of a diastereoselective intermolecular synthesis method for alkyl ethers using reductive etherification of various ketones or aldehydes with alcohols. The key aspect of this development is the utilization of low-temperature high-throughput experimentation (HTE) technologies for rapid reaction optimization and parallel synthesis. By carefully selecting the reductant, the diastereoselectivity of this transformation can be easily controlled.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Yu Li, Na Hu, Zefei Xu, Yunfeng Cui, Jinhui Feng, Peiyuan Yao, Qiaqing Wu, Dunming Zhu, Yanhe Ma
Summary: The enzymatic asymmetric reductive amination process can be used to convert simple aldehydes and amines into chiral N-substituted 1,2-amino alcohols, providing an environmentally friendly and economical method.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Organic
Guoling Huang, Xunbo Lu, Kaiyuan Yang, Xinyu Xu
Summary: In this study, a metal-free and redox-neutral strategy was developed for the selective S-alkylation of sulfenamides under basic conditions to yield sulfilimines. The key step involves the resonance between bivalent nitrogen-centered anions, generated after deprotonation of sulfenamides under alkaline conditions, and sulfinimidoyl anions. Our sustainable and efficient approach employs sulfur-selective alkylation of readily accessible sulfenamides and commercially available hydrocarbons, leading to the successful synthesis of 60 sulfilimines in high yields (36-99%) and short reaction times.
Article
Chemistry, Organic
Thorsten Kinsinger, Uli Kazmaier
Summary: The Matteson homologation with vinyl nucleophiles is a versatile tool for synthesizing highly substituted and functionalized allyl boronic esters. It provides high yields and stereoselectivities, especially with sterically demanding alkyl boronic esters and/or Grignard reagents. This method has been successfully applied in the synthesis of the polyketide fragment of lagunamide B.
Article
Chemistry, Organic
Feng Yu, Renqing Tao, Yiting Su, Guixia Liu, Zheng Huang
Summary: Direct asymmetric alkyl group functionalizations convert hydrocarbon feedstocks into chiral fine chemicals. A strategy based on dehydrogenation enables enantioselective formal benzylic C(sp(3))-H bond borylation to produce benzylic boronate esters with excellent site- and enantioselectivity.
Article
Chemistry, Physical
William Finnigan, Lorna J. Hepworth, Sabine L. Flitsch, Nicholas J. Turner
Summary: With the expanding enzyme toolbox for biocatalysis, there is potential for constructing powerful enzymatic cascades for efficient and selective synthesis of target molecules. RetroBioCat is an intuitive tool for computer-aided design of biocatalytic cascades, utilizing expertly encoded reaction rules and literature precedent to identify promising biocatalytic pathways.
Article
Chemistry, Organic
Yougourthen Boumekla, Fengjie Xia, Lucas Vidal, Cedric Totee, Christophe Raynaud, Armelle Ouali
Summary: A method to reduce aldimines via hydrosilylation using a catalytic system of calcium triflimide and potassium hexafluorophosphate is reported, achieving high yields in mild conditions. Additionally, a bioactive molecule with antifungal properties was successfully synthesized on a large scale in environmentally friendly solvent. The mechanism involves electrophilic activation of the silane by the calcium catalyst, as confirmed by experimental and DFT calculations.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2023)
Article
Chemistry, Organic
Raphael K. Klake, Mytia D. Edwards, Joshua D. Sieber
Summary: A new catalytic enantioselective addition method utilizing copper-catalyzed reductive coupling to add N-substituted allyl equivalents to ketones has been developed, accessing important chiral 1,2-aminoalcohol synthons with high levels of regio-, diastereo-, and enantioselectivity. Factors affecting enantioinduction are discussed, including the identification of a reversible ketone allylation step previously unreported in copper-catalyzed reductive coupling.
Review
Chemistry, Multidisciplinary
Yaru Gao, Guorong Hong, Bin-Miao Yang, Yu Zhao
Summary: Direct substitution of readily available alcohols is an important area of research in green chemical synthesis. Catalytic enantioconvergent transformations of racemic secondary alcohols are desired for efficient access to valuable enantiopure compounds. The enantioconvergent borrowing hydrogen methodology has proven to be effective for achieving such transformations. This review provides an overview of the progress made in the past decade, focusing on the conversion of racemic secondary alcohols to enantioenriched chiral amines, N-heterocycles, higher-order alcohols, and ketones.
CHEMICAL SOCIETY REVIEWS
(2023)
Article
Chemistry, Organic
Narendra Bisht, Prabhakar Singh, Srinivasarao Arulananda Babu
Summary: In this paper, we report the expansion of the library of enantiopure alpha-methylbenzylamine and phenylglycinol scaffolds through Pd(II)-catalyzed sp(2) gamma-C-H functionalization. Various racemic and enantiopure derivatives were synthesized with good enantiopurities, making them important building blocks in organic synthesis and medicinal chemistry.
SYNTHESIS-STUTTGART
(2022)
Article
Chemistry, Multidisciplinary
Steve H. Park, Geunsu Bae, Ahhyeon Choi, Suyeon Shin, Kwangmin Shin, Chang Hyuck Choi, Hyunwoo Kim
Summary: This study presents an electrocatalytic approach for the intramolecular hydroamination of allylic sulfonamides to access azetidines. The combination of cobalt catalysis and electricity enables the regioselective generation of key carbocationic intermediates, which undergo intramolecular C-N bond formation. Mechanistic investigations suggest that catalyst regeneration by nucleophilic cyclization or the second electrochemical oxidation to access the carbocationic intermediate is involved in the rate-determining step (RDS) of the electrochemical protocol.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Suresh Rajamanickam, Mayank Saraswat, Sugumar Venkataramani, Bhisma K. Patel
Summary: A distal selectivity in appended alkyl chains based on intermolecular radicals has been developed, with the highest selectivity observed when the distal carbon is at the gamma position. The selectivity decreases as the position moves from gamma to delta to epsilon. Computational predictions suggest that radical stability and kinetic barriers are responsible for these trends. This strategy does not rely on designer catalysts, and the selectivity is determined by the intrinsic reactivity of the substrate.
Review
Chemistry, Multidisciplinary
Sergio Gonzalez-Granda, Jesus Albarran-Velo, Ivan Lavandera, Vicente Gotor-Fernandez
Summary: The combination of metal-, photo-, enzyme-, and/or organocatalysis is a versatile approach in synthetic chemistry, particularly for the creation of chiral centers. This review focuses on the recent developments in the simultaneous use of enzymes and transition metal catalysts, as well as the integration of multiple bioprocesses and metal-catalyzed transformations in linear cascades. Challenges such as catalyst compatibility, reaction media, and cross-reactivities are addressed by strategies such as catalyst coimmobilization, compartmentalization, and flow chemistry. The review also highlights the application of bionanohybrid materials, where enzymes and metals are coimmobilized on suitable supports.
Article
Chemistry, Applied
Laura Rodriguez-Fernandez, Jesus Albarran-Velo, Ivan Lavandera, Vicente Gotor-Fernandez
Summary: The photocatalytic Meerwein arylation between aromatic diazonium salts and isopropenyl acetate in aqueous medium was studied under blue LED light irradiation. Optimization of reaction conditions allowed the synthesis of various 1-arylpropan-2-ones with up to 95% yield using [Acr-Mes]ClO4 as the photocatalyst. Furthermore, a one-pot sequential photobiocatalytic approach combining the Meerwein arylation with bioreduction of ketone intermediates was developed, leading to the synthesis of 1-arylpropan-2-ol enantiomers with up to 76% overall yield and high stereoselectivity.
ADVANCED SYNTHESIS & CATALYSIS
(2023)
Article
Chemistry, Applied
Sergio Gonzalez-Granda, Georg Steinkellner, Karl Gruber, Ivan Lavandera, Vicente Gotor-Fernandez
Summary: The combination of gold(I) and enzyme catalysis allows for the selective synthesis of a series of nor(pseudo)ephedrine derivatives. This approach involves the hydration of 1-phenylprop-2-yn-1-yl acetate or N-(1-phenylprop-2-yn-1-yl)acetamide using IPrAuNTf2 catalyst, followed by (dynamic) asymmetric biotransamination or bioreduction of the resulting keto ester or keto amide intermediates. Enzyme actions exhibit high stereoselectivity towards methyl ketones, enabling the synthesis of enantio- and diastereomerically enriched products. The use of propargyl esters or amides as starting materials allows for the production of amino alcohol, diol, and diamine derivatives with good yields and high (stereo)selectivity.
ADVANCED SYNTHESIS & CATALYSIS
(2023)
Review
Chemistry, Multidisciplinary
Sergio Gonzalez-Granda, Lorena Escot, Ivan Lavandera, Vicente Gotor-Fernandez
Summary: The combination of metal and enzyme catalysis has attracted great attention in organic synthesis due to its ability to achieve diverse organic molecules with the stereospecificity displayed by enzymes. This minireview focuses on the action of metal species (Pd, Ru, Au, Ir, Fe, etc.) in combination with different enzymes, highlighting the design of sequential processes and concurrent cascades to overcome incompatibilities.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Nicoletta Cascelli, Vincenzo Lettera, Giovanni Sannia, Vicente Gotor-Fernandez, Ivan Lavandera
Summary: Laccases are shown to be valuable in biocatalysis for the green and selective oxidation of furfuryl alcohol into furfural using mediators. Various parameters including pH, enzyme/mediator composition, buffer type, cosolvent tolerance, and reaction times are investigated. Under optimal conditions, quantitative production of furfural is achieved after 16 h using 20 mol % of TEMPO as mediator and 5.8 U mL(-1) of POXC and POXA1b laccases from Pleurotus ostreatus. POXC exhibits remarkable catalytic ability at pH 6.5, while POXA1b is notable for its high stability. Furfural conversions of up to 95% are obtained after 72 h using only 5 mol % of TEMPO at 100 mM. Furthermore, furfuryl alcohol bioamination is successfully achieved through a one-pot sequential approach using amine transaminase from Chromobacterium violaceum, providing furfuryl amine, a key compound for the polymer industry.
Article
Biochemistry & Molecular Biology
Antia Pintor, Nicoletta Cascelli, Alexey Volkov, Vicente Gotor-Fernandez, Ivan Lavandera
Summary: This study discloses the biocatalytic amination of furan-based compounds using amine transaminases (ATAs) and isopropylamine (IPA) as amine donors. Optimal biocatalysts were identified and high levels of product formation were achieved. pH was found as a key factor affecting the transformation.
Article
Chemistry, Multidisciplinary
Antia Pintor, Ivan Lavandera, Alexey Volkov, Vicente Gotor-Fernandez
Summary: The study focused on finding an ideal biocatalyst for the acylation of furfurylamine and 5-hydroxymethylfurfurylamine (HMFA), and identified immobilized Candida antarctica lipase B (CALB) as a suitable option. CALB was immobilized on different supports and the use of a polymer-coated controlled porosity glass carrier material yielded an active and stable enzymatic preparation for the acylation reaction. By controlling the amount of acyl donor in the reaction, selective modification of the amine group of HMFA was achieved, resulting in the formation of hydroxy amides. The reaction conditions and substrate concentration were optimized to achieve high conversions and yields. The study also demonstrated the possibility of obtaining orthogonally protected HMFA-derived amido esters through a one-pot process.
ACS SUSTAINABLE CHEMISTRY & ENGINEERING
(2023)
Article
Chemistry, Multidisciplinary
Antia Pintor, Ashley P. Mattey, Ivan Lavandera, Vicente Gotor-Fernandez, Alexey Volkov
Summary: The use of multienzymatic systems has become popular for complex (asymmetric) syntheses. Incompatible substrates, reagents, and enzymes can limit the applicability of a cascade reaction in batch conditions, so flow systems are preferred. Immobilized enzymes in continuous flow reactors enable the segregation and isolation of enzymes, allowing for otherwise challenging reaction cascades.
Article
Biochemistry & Molecular Biology
Nicoletta Cascelli, Vicente Gotor-Fernandez, Ivan Lavandera, Giovanni Sannia, Vincenzo Lettera
Summary: Modern biocatalysis relies on fast and efficient screening methods to find novel biocatalysts for chemical production. This study introduces a colorimetric assay using Schiff-based polymers to detect the presence of DFF in reaction mixtures.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)
Article
Chemistry, Multidisciplinary
Xuemei Liu, Chaonan Cui, Shuoshuo Wei, Jinyu Han, Xinli Zhu, Qingfeng Ge, Hua Wang
Summary: This study presents a new strategy for designing efficient photocatalysts that can convert CO2 into hydrocarbons by utilizing synergistic catalytic sites. The findings provide a solution for the selective photocatalytic reduction of CO2 to CH4.
Article
Chemistry, Multidisciplinary
Chengxian Hu, Dan Wang, Lu Wang, Ying Fu, Zhengyin Du
Summary: A novel one-pot, three-component reaction conducted under electrochemical conditions was studied. The reaction involved 2-aminothiophenols, aldehydes, and malononitrile, using TBABF4 as an electrolyte and CuI as a catalyst. The proposed reaction mechanism suggested that CuI served as an electron relay. This method offers simplified operation, high atom economy, and mild reaction conditions.
Article
Chemistry, Multidisciplinary
Zhi Yang, Yu Chen, Linxi Wan, Yuxiao Li, Dan Chen, Jianlin Tao, Pei Tang, Fen-Er Chen
Summary: A highly enantioselective method for the complete hydrogenation of pyrimidinium salts using Ir/(S,S)-f-Binaphane complex as the catalyst was developed. This method provides easy access to fully saturated chiral hexahydropyrimidines, which are prevalent in many bioactive molecules. The reactions exhibit high yields and enantioselectivities under mild reaction conditions without additives. Successful application of this methodology in a continuous flow fashion further extends its practical utility.
Article
Chemistry, Multidisciplinary
Tina Jeoh, Jennifer Danger Nill, Wujun Zhao, Sankar Raju Narayanasamy, Liang Chen, Hoi-Ying N. Holman
Summary: In this study, the enzymatic hydrolysis of cellulose was investigated using real-time infrared spectromicroscopy. The spatial heterogeneity of cellulose was found to impact the hydrolysis kinetics. Hydration affected cellulose ordering, and Cel7A preferentially removed less extensively hydrogen bonded cellulose.
Article
Chemistry, Multidisciplinary
Tiphaine Richard, Walid Abdallah, Xavier Trivelli, Mathieu Sauthier, Clement Dumont
Summary: An effective method of grafting functionalities onto lignin based on glycerol carbonate has been developed using an efficient nickel-catalysed telomerisation reaction. This method allows lignin to have new reactive functions and reduces the glass transition temperatures of modified lignins, thereby expanding the application range of lignin-based resins.
Article
Chemistry, Multidisciplinary
Jing Qi, Xiyan Wang, Gan Wang, Srinivas Reddy Dubbaka, Patrick ONeill, Hwee Ting Ang, Jie Wu
Summary: This study presents a green and environmentally friendly approach for the synthesis of imides using electrocatalytic oxidation with H2O as the oxygen source. The method eliminates the need for toxic or expensive oxidants and achieves high yields under mild reaction conditions. It shows broad substrate compatibility and potential for industrial applications.
Article
Chemistry, Multidisciplinary
Babasaheb Sopan Gore, Lin-Wei Pan, Jun-Hao Lin, Yi-Chi Luo, Jeh-Jeng Wang
Summary: Here, we report a visible light-promoted intramolecular radical cascade reaction for the construction of fluorenol and naphthalene-fused cyclopropyl carbaldehyde derivatives. This method offers mild reaction conditions, a broad substrate scope, excellent step efficiency, and scalability, without the need for external chemical oxidants. The novelty of this protocol was demonstrated by synthesizing chrysene analogs and performing late-stage functionalizations.
Article
Chemistry, Multidisciplinary
Juho Antti Sirvio, Idamaria Romakkaniemi, Juha Ahola, Svitlana Filonenko, Juha P. Heiskanen, Ari Ammala
Summary: This article discusses the method of using supramolecular interaction between an aromatic hydrogen bond donor and lignin to achieve rapid delignification of softwood at low temperatures.
Article
Chemistry, Multidisciplinary
Yunyan Meng, Chunxiang Pan, Na Liu, Hongjiang Li, Zixiu Liu, Yao Deng, Zixiang Wei, Jianbin Xu, Baomin Fan
Summary: A novel visible light-driven synthesis method for 2,3-diamines has been developed, which has mild conditions, avoids the use of metal reagents, and can synthesize diamines and diols in one pot.
Article
Chemistry, Multidisciplinary
Mingqing Huang, Haiyang Huang, Mengyao You, Xinxin Zhang, Longgen Sun, Chao Chen, Zhichao Mei, Ruchun Yang, Qiang Xiao
Summary: A direct air-oxidized strategy for the synthesis of benzo[b]phosphole oxides was developed in this study. Arylphosphine oxides were transformed into phosphinoyl radicals, which were further combined with various alkynes to achieve the desired products. DFT calculations revealed the mechanism of phosphinoyl radical formation.
Article
Chemistry, Multidisciplinary
Anwei Wang, Jiayin Huang, Chunsheng Zhao, Yu Fan, Junfeng Qian, Qun Chen, Mingyang He, Weiyou Zhou
Summary: This study demonstrates an innovative strategy for the aerobic oxidation of C(sp(3))-H bonds using gamma-valerolactone. By optimizing the reaction conditions and utilizing specific catalysts, efficient oxidation of C(sp(3))-H bonds is achieved with good chemoselectivity in certain cases.
Article
Chemistry, Multidisciplinary
Shun Li, Likai Tong, Zhijian Peng, Bo Zhang, Xiuli Fu
Summary: Sulfide compounds show promise as electrocatalysts for water splitting, but their performance is limited by factors such as limited active sites and hindered substance transport. This study successfully prepared a high-entropy sulfide (ZnCoMnFeAlMg)(9)S-8, which reduced grain size and increased specific surface area, enabling the realization of a dual-functional catalyst with multiple catalytic sites. High entropy also modulated the electronic properties of sulfides, reducing the potential energy barrier for hydrolysis. This research introduces a new approach for functionalizing high entropy nanomaterials and improves the performance of water splitting catalysts.
