Article
Chemistry, Organic
Barbara Mohar, Marko Jeran, Michel Stephan
Summary: Outfitting the 2MeBigFUS ligand with the branched/functionalized-alkoxy feature of the R-SMS-Phos design resulted in the 2RBigFUS family. Rhodium(I) complexes of these ligands exhibited enhanced activity and superior enantioselectivity in the hydrogenation of functionalized olefins, including challenging α-arylacrylic acids. The application of these catalysts to enantiomeric active pharmaceutical ingredients (APIs) and synthetic building blocks further highlighted their potential.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Jianfei Yu, Haowei Zhu, Xumu Zhang, Gen-Qiang Chen
Summary: A new series of chiral ferrocene-based diphosphino-ethane ligands, f-DPE, were developed and applied in the hydrogenation of 2-substituted acrylic acids to obtain chiral propanoic acids with high yields and enantioselectivities. The synthesis of well-known anti-inflammatory drugs, such as ibuprofen, naproxen, and flurbiprofen, was also efficiently achieved using this method. The synthetic utilities of the method were demonstrated through gram-scale experiments.
Article
Chemistry, Inorganic & Nuclear
Nora Jannsen, Christian Fischer, Carmen Selle, Cornelia Pribbenow, Hans-Joachim Drexler, Fabian Reiss, Torsten Beweries, Detlef Heller
Summary: In this study, we systematically investigate and quantify the influence of solvent coordination on reactions of cationic rhodium(i) diphosphine complexes. We propose a method to analyze and quantify solvent binding using MeCN as a replacement for diolefins. By using UV-vis and P-31{H-1} NMR spectroscopy, we determine and compare stability constants of different complexes, and discuss the impact of different ligands and reaction temperature. DFT study reveals the relationship between stability and thermodynamics of the exchange reaction. Additionally, variable temperature NMR spectroscopy confirms the existence of a mixed solvate complex as an intermediate in the MeCN-MeOH exchange.
DALTON TRANSACTIONS
(2022)
Article
Chemistry, Inorganic & Nuclear
Kristina Zivkovic, Lilia M. Baldauf, Jessica L. Cryder, Alexa Villasenor, Valeria Reyes, Lauren E. Bernier, Theresa J. Thomas, Maxwell O'Toole, Kayleen Fulton, Curtis E. Moore, Arnold L. Rheingold, Christopher J. A. Daley
Summary: The study reports the first isolation and structural characterization of a series of chiral trinitrogen pincer ligands, as well as the methods for their preparation. Experimental results show that a novel microwave-based technique is more efficient, although currently not scalable.
DALTON TRANSACTIONS
(2021)
Article
Chemistry, Multidisciplinary
Yulong Zhang, Peichao Zhao, Shengnan Sun, Qian Wu, Enxue Shi, Junhua Xiao
Summary: The authors developed a camphor-derived 2,3-diol as a chiral template to synthesize diverse P(III) and P(V) chiral compounds, which are highly desirable for asymmetric catalysis in organic chemistry.
COMMUNICATIONS CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Juana M. Perez, Roxana Postolache, Marta Castineira Reis, Esther G. Sinnema, Denisa Vargova, Folkert de Vries, Edwin Otten, Luo Ge, Syuzanna R. Harutyunyan
Summary: Chiral Mn(I) complexes have been shown to activate H-P bonds, providing a general method for the hydrophosphination of internal and terminal alpha,beta-unsaturated nitriles. Metal-ligand cooperation, a previously unconsidered strategy for catalytic H-P bond activation, plays a key role in the mechanistic action of the Mn(I)-based catalyst. Computational studies support a stepwise mechanism for the hydrophosphination reaction and offer insights into the origin of enantioselectivity.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Review
Chemistry, Inorganic & Nuclear
Jessica Margalef, Maria Biosca, Pol de la Cruz Sanchez, Jorge Faiges, Oscar Pamies, Montserrat Dieguez
Summary: The success of phosphine-oxazoline ligands has led to advancements in P-oxazoline ligand families, resulting in diverse structures and more efficient ligands for asymmetric transformations. Through proper design, these heterodonor bidentate ligand families exhibit superior catalytic performance in a variety of asymmetric reactions.
COORDINATION CHEMISTRY REVIEWS
(2021)
Article
Chemistry, Organic
Jan-Michael Menke, Oliver Trapp
Summary: For the preparation of chiral drugs, the combination of stereochemically stable and flexible catalysts with chiral auxiliaries is crucial. In this study, a successful approach to the spontaneous deracemization of tropos ligands for asymmetric catalysis was demonstrated.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Physical
Ricardo Molina Betancourt, Lucas Bacheley, Anzhela Karapetyan, Gerard Guillamot, Phannarath Phansavath, Virginie Ratovelomanana-Vidal
Summary: The Rh(III)-catalyzed asymmetric reduction of alpha-trifluoromethyl ketones through transfer hydrogenation was developed under mild conditions. It enables a dynamic kinetic resolution process to access a series of enantioenriched cis-trifluoromethyl alcohols. The reaction was performed efficiently in the green solvent 2-MeTHF using HCO2H/Et3N (1 : 1) as the hydrogen source. High yields and excellent diastereo- and enantioselectivities were achieved for the synthesis of CF3-chromanol, CF3-indanol, and CF3-tetralol derivatives.
Review
Chemistry, Multidisciplinary
Cai Zhang
Summary: This review comprehensively summarizes the application of bisphospholane Josiphos-type ligands in rhodium asymmetric catalysis, including asymmetric addition, asymmetric hydrogenation, and asymmetric silanization reactions.
CHEMISTRY-AN ASIAN JOURNAL
(2023)
Article
Chemistry, Organic
Tushar Janardan Pawar, Liliette Barcelona-Cazanave, Israel Bonilla-Landa, Magdalena Escobar, J. Oscar C. Jimenez-Halla, Alma Altuzar-Molina, Patricia Romero-Arellano, Andrew J. F. Edmunds, Martin Aluja, Jose Luis Olivares-Romero
Summary: This study presents a highly efficient iridium-catalyzed asymmetric hydrogenation approach for the total synthesis of biologically active (R,L) A. ludens host marking pheromone (HMP). The use of a novel Ir(i)-complex and a chiral P,N-ligand resulted in excellent enantioselectivities of up to 94% ee. The streamlined synthetic route involving seven reaction steps offers improved efficiency and shorter synthesis timelines compared to previous methods.
ORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Physical
Vidmantas Bieliunas, Sigitas Stoncius
Summary: The design and synthesis of second generation C-2-symmetric ligands with additional substituents was reported. These substituents provide a further element for fine-tuning the ligand structure by enforcing conformational rigidity. The tetrasubstituted bicyclo[3.3.1]nona-2,6-dienes were successfully employed in the rhodium-catalyzed arylation reaction with good to excellent yields and enantioselectivities up to 99% ee.
Article
Chemistry, Multidisciplinary
Qiwei Lang, Huaxin Yang, Guoxian Gu, Qiang Feng, Jialin Wen, Xumu Zhang
Summary: In this study, an efficient method for reducing endocyclic enones with high enantioselectivity using molecular hydrogen catalyzed by a rhodium/Zhaophos complex is reported. This method demonstrated excellent chemo- and enantioselectivity and was successfully applied in the enantioselective hydrogenation of citral to produce enantiomer-enriched citronellal.
CHINESE JOURNAL OF CHEMISTRY
(2021)
Article
Chemistry, Organic
Pep Rojo, Antoni Riera, Xavier Verdaguer
Summary: The efficient electrophilic P-stereogenic transfer reagent BOM-tert-butylmethylphosphinite borane was used for the synthesis of bulky tertiary phosphines with high stereospecificity in a one-pot deprotection/substitution reaction. A wide range of tertiary phosphines in excellent enantiomeric excess was synthesized using this method, including a bulky P-stereogenic BisP* ligand analogue.
Article
Chemistry, Multidisciplinary
Jan-Michael Menke, Katharina Scholz, Oliver Trapp
Summary: Novel l-tartaric acid based stereodynamic biphenylbisphosphinite ligands with anilino linkers were prepared and the influence of different amino group substitution patterns on the selective formation of the ligand was investigated. Experimental results showed that ortho-anilino bridged ligands exhibited high diastereoselectivity in rhodium-catalyzed reactions.
HELVETICA CHIMICA ACTA
(2021)
Article
Chemistry, Inorganic & Nuclear
Javier Eusamio, Yaiza M. Medina, Javier C. Cordoba, Anton Vidal-Ferran, Daniel Sainz, Albert Gutierrez, Merce Font-Bardia, Arnald Grabulosa
Summary: Enantiopure P-stereogenic methylphosphane-boranes have been used to prepare organometallic compounds with chiral phosphine ligands. These compounds exhibit good catalytic activity and selectivity in hydrogenation and transfer hydrogenation reactions.
DALTON TRANSACTIONS
(2023)
Article
Chemistry, Inorganic & Nuclear
Evangelos Pilichos, Annia Tubau, Saskia Speed, Merce Font-Bardia, Albert Escuer, Arnald Grabulosa, Julia Mayans
Summary: A new family of lanthanide compounds with different structures and properties have been synthesized using dppeO(2) as a ligand. The compounds exhibit a two-dimensional or one-dimensional structure depending on the lanthanide cation. Some of the compounds have magnetic or luminescent properties, and they can be used as structural probes or for specific applications.
DALTON TRANSACTIONS
(2023)
Article
Chemistry, Applied
Albert Martinez-Segura, Javier Eusamio, Yaiza M. Medina, Katherine Ariz, Albert Gutierrez, Joan Albert, Jaume Granell, Merce Font-Bardia, Arnald Grabulosa
Summary: Cycloruthenated complexes C1-C5 have been synthesized cleanly by the reaction of N-(benzylidene)benzylamines (p-RC6H4CH=NCH2C6H5; R = Cl, H, NO2, F, OMe) with [RuCl2(eta(6)-p-cymene)](2) and potassium acetate. The process exhibits complete regioselectivity, yielding the endo-derivative regardless of the substituent on the aromatic ring. The enantiopure imines (R-C)-p-RC6H4CH=NCHMeC10H7 (R = Cl, H) can also form five-membered endo-metallacycles C6 and C7 under similar conditions. The crystal structures of all seven metallated compounds have been determined by X-ray diffraction. These complexes serve as effective catalyst precursors for the transfer hydrogenation of acetophenone and benzophenone, with complex C7 achieving up to 77% enantiomeric excess at room temperature.
APPLIED ORGANOMETALLIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Marina Bellido, Carlos Riego-Mejias, Alejandro Diaz-Moreno, Xavier Verdaguer, Antoni Riera
Summary: A novel method for preparing chiral methyl benzylic compounds is described, involving the preparation of terminal homoallyl sulfones from homoallyl alcohols through Lewis acid isomerization of oxetanes. Asymmetric hydrogenation of these homoallylic sulfones using an iridium catalyst yielded gamma-chiral sulfones with high enantioselectivities (up to 98% ee). The synthetic potential of this method was demonstrated through the total synthesis of (R)-(-)-curcumene.
Article
Chemistry, Physical
Maria Biosca, Pol de la Cruz-Sanchez, Jorge Faiges, Jessica Margalef, Ernest Salomo, Antoni Riera, Xavier Verdaguer, Joan Ferre, Feliu Maseras, Maria Besora, Oscar Pamies, Montserrat Dieguez
Summary: Ir-MaxPHOX-type catalysts exhibit high catalytic performance in the hydrogenation of a wide range of nonchelating olefins with different geometries, substitution patterns, and degrees of functionalization. These air-stable and readily available catalysts have been successfully used in the asymmetric hydrogenation of di-, tri-, and tetrasubstituted olefins (ee ' s up to 9996). The combination of theoretical calculations and deuterium labeling experiments has revealed the factors responsible for the observed enantioselectivity, allowing for the rationalization of suitable substrates for these Ircatalysts.
Article
Nanoscience & Nanotechnology
Jose Luis Nunez-Rico, Juanjo Cabezas-Gimenez, Vanesa Lillo, Salvador R. G. Balestra, Jose Ramoon Galan-Mascaros, Sofia Calero, Anton Vidal-Ferran
Summary: Metal-organic frameworks (MOFs) with tunable properties and controlled dimensionality have shown promising potential for various applications. The incorporation of chirality into MOFs opens up new strategies for chiral separation, which is crucial in the pharmaceutical industry. In this study, computational modeling and experiments were combined to demonstrate the efficiency, versatility, robustness, and reusability of TAMOF-1-packed HPLC columns as the chiral stationary phase. The in silico studies predicted plausible separations of chiral compounds from different families, and the experimental results confirmed the validity of the models and the high performance of TAMOF-1 columns. The use of in silico screening in chiral chromatography is an unprecedented achievement.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Review
Chemistry, Inorganic & Nuclear
Pep Rojo, Antoni Riera, Xavier Verdaguer
Summary: Since the development of BisP* ligand by Imamoto, P-stereogenic phosphines bearing a bulky tert-butyl group and a smaller alkyl group have shown remarkable performance in various asymmetric processes. Advances in this class of ligands include the introduction of more rigid backbones, the three-hindered quadrant concept, and the substitution of tert-butyl group with adamantyl. The industrial sector has also contributed by reporting successful P-stereogenic Buchwald-type monophosphines for asymmetric coupling reactions. This review focuses on the synthesis and applications of bulky P-stereogenic phosphines developed since the late 1990s, with a special emphasis on ligands successfully applied in asymmetric catalysis.
COORDINATION CHEMISTRY REVIEWS
(2023)
Article
Chemistry, Physical
Alba Martinez-Bascunana, Jose Luis Nunez-Rico, Lucas Carreras, Anton Vidal-Ferran
Summary: The choice of counterion has a significant impact on metal-catalyzed reactions, as it can modify the performance of the catalyst and influence the reaction rate and selectivity. In this study, the effects of counterion variation in cationic halogen bond-assembled Rh(I) catalysts in the hydroboration reaction of terminal alkynes were investigated. It was found that higher coordination ability of the counterion led to higher activity and selectivity towards hydroboration products, which was demonstrated through catalytic and spectroscopic studies. The practicality of the synthetic method was demonstrated by developing one-pot hydroboration/Csp2-Csp2 coupling processes.
Article
Chemistry, Inorganic & Nuclear
Dana Josa, David Aguila, Pere Fontova, Vanessa Soto-Cerrato, Piedad Herrera-Ramirez, Laia Rafols, Arnald Grabulosa, Patrick Gamez
Summary: Five metal-arene complexes and nine cyclometalated half-sandwich complexes were synthesized, characterized, and evaluated for cytotoxicity against human cancer cells. The complexes showed notable cytotoxic properties, particularly against lung adenocarcinoma cells. One of the complexes also exhibited significant toxic effects on other cell lines. Furthermore, the study identified a complex that impacted the cell cycle of lung adenocarcinoma cells.
DALTON TRANSACTIONS
(2023)
Article
Chemistry, Multidisciplinary
Enric Ros, Marina Bellido, Joan A. Matarin, Albert Gallen, Manuel Martinez, Laura Rodriguez, Xavier Verdaguer, Lluis Ribas de Pouplana, Antoni Riera
Summary: A set of 3-bromo-1,2,4,5-tetrazines with distinct substitutions have been used as reagents for late-stage functionalization. Spectroscopic studies showed that tetrazine ethers are intrinsically fluorescent and this fluorescence can be lost through iEDDA cycloaddition. Tetrazine-phenol ethers can undergo rapid iEDDA reactions with a second order rate constant compatible with bioorthogonal ligations. The coupling of 3-bromo-6-methyl-1,2,4,5-tetrazine with l-tyrosine and octreotide demonstrated the detection and reactivity of intrinsically fluorescent tetrazines in a biologically relevant context. The synthesis and characterization of fluorescent tetrazine ethers with bioorthogonal applicability pave the way for the generation of useful compounds for both detection and bioconjugation in vivo.
