Article
Chemistry, Multidisciplinary
Stuart C. D. Kennington, Saul F. Teloxa, Miguel Mellado-Hidalgo, Oriol Galeote, Sabrina Puddu, Marina Bellido, Pedro Romea, Felix Urpi, Gabriel Aullon, Merce Font-Bardia
Summary: A direct and asymmetric aldol reaction of N-acyl thiazinanethiones with aromatic aldehydes catalyzed by chiral nickel(II) complexes was reported. The reaction gives high yields of O-TIPS-protected anti-aldol adducts with remarkable stereocontrol and atom economy. The removal of the achiral scaffold provides enantiomerically pure intermediates with synthetic interest for producing anti-alpha-amino-beta-hydroxy and alpha,beta-dihydroxy carboxylic derivatives, with theoretical calculations explaining the observed high stereocontrol.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Nanoscience & Nanotechnology
Miguel Sanchez-Fuente, Alberto Lopez-Magano, Alicia Moya, Ruben Mas-Balleste
Summary: Condensation of BINAPO-(PhCHO)(2) and 1,3,5-tris(4-aminophenyl)benzene(TAPB) leads to a new imine-based chiral organic material (COM) that can be post-functionalized through reductive transformation of imine linkers to amines. Although the imine-based material is not stable enough to be used as a heterogeneous catalyst, the reduced amine-linked framework can be efficiently utilized in asymmetric allylation of various aromatic aldehydes. The obtained yields and enantiomeric excesses are comparable to those observed for the molecular BINAP oxide catalyst, with the added advantage of recyclability offered by the amine-based material.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Organic
Isaac G. Sonsona, Andrea Vicenzi, Marco Guidotti, Giorgiana Denisa Bisag, Mariafrancesca Fochi, Raquel P. Herrera, Luca Bernardi
Summary: The study demonstrates the improved selectivity of an asymmetric aldol reaction by replacing part of the catalyst, and identifies the most suitable reaction conditions. However, these conditions seem to be limited to oxindoles bearing a 3-substituent of funapide.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Physical
William R. R. Cassels, Evan T. T. Crawford, Jeffrey S. S. Johnson
Summary: We report a simple catalytic crystallization-driven enantio- and diastereoselective Mannich reaction for the synthesis of stereodefined alpha-monosubstituted-ss-ketoesters, dissymmetric ss-diesters, dissymmetric ss-diketones, and ss-keto amides. This method efficiently leverages product epimerization in solution. Mechanistic studies suggest that the initial enantioselective, diastereodivergent skeletal assembly is catalyzed by a chiral tertiary amine organocatalyst, followed by crystallization-induced diastereoconvergence to provide the challenging alpha-stereocenter in excellent stereoselectivity.
Article
Biochemistry & Molecular Biology
Ciril Jimeno
Summary: The research was inspired by the binding and stabilizing effect of arginine residues in certain aldolases, leading to the development of a new family of amino acylguanidine organocatalysts. Screening and optimization identified the threonine derivative as the most suitable catalyst for asymmetric aldol addition, while the proline derivative yielded the anti diastereomer. MMFF models indicated the presence of an extensive hydrogen bonding network between the acylguanidinium group and the reaction intermediates.
Article
Chemistry, Physical
Jeffrey S. Johnson, William R. Cassels, Evan T. Crawford
Summary: A simple catalytic crystallization-driven enantio- and diastereoselective Mannich reaction was disclosed for the synthesis of stereodefined alpha-monosubstituted-keto esters, dissymmetric diesters, dissymmetric diketones, and keto amides that productively leveraged product epimerization in solution. Mechanistic studies suggested that the initial enantioselective, diastereodivergent skeletal assembly was catalyzed by a chiral tertiary amine organocatalyst, which then facilitated second stage crystallization-induced diastereoconvergence to provide the challenging alpha-stereocenter in excellent stereoselectivity.
Review
Chemistry, Applied
Sara Meninno, Francesca Franco, Maurizio Benaglia, Alessandra Lattanzi
Summary: Pyrazoleamides have gained attention as reactive and practical surrogates in asymmetric catalysis, particularly in a variety of metal- and organocatalytic transformations. Their relevance has extended to photoredox catalysis and challenging stereoselective bond-forming reactions in recent years.
ADVANCED SYNTHESIS & CATALYSIS
(2021)
Article
Chemistry, Multidisciplinary
Ingolf Harden, Frank Neese, Giovanni Bistoni
Summary: The formation of Bronsted acid aggregates in asymmetric organocatalytic reactions has a significant impact on the stereo-controlling factors of the transformations. This study uses high-level quantum mechanical calculations to investigate the influence of catalyst structure and reaction conditions on the spontaneity of the aggregation process, shedding light on its importance.
Article
Chemistry, Multidisciplinary
Ingolf Harden, Frank Neese, Giovanni Bistoni
Summary: This study investigates the aggregation process of chiral organocatalysts derived from phosphoric acids using high-level quantum mechanical calculations. The results show that the formation of catalyst dimers is possible and the aggregation process can significantly affect the stereo-controlling factors, reaction kinetics, and selectivity of the transformations.
Article
Chemistry, Physical
Liangliang Zhang, Martin Oestreich
Summary: The passage describes a reaction sequence involving enantioselective copper-catalyzed conjugate silylation and diastereotopic group-selective aldol cyclization. The intramolecular aldol reaction's diastereoselectivity depends on the silicon nucleophile used, and the more basic zinc reagent enables thermodynamically driven cis-to-trans isomerization. A wide range of electron-withdrawing groups, including electron-deficient heterocycles, are compatible with the different procedures developed.
Article
Biochemistry & Molecular Biology
Dong-Hua Xie, Cheng Niu, Da-Ming Du
Summary: In this paper, a new protocol for building a chiral ring-fused chroman skeleton was developed through organocatalytic asymmetric Michael addition/hemiketalization cascade reactions. The reactions provided chiral chroman-fused pyrrolidinediones with high yields and excellent stereoselectivities. A scale-up synthesis was also conducted, and a possible reaction mechanism was proposed.
Article
Chemistry, Organic
Gen-Fa Wen, Rui Zhang, Chu-Yu Zhang, Chao-Shan Da
Summary: This study compares and explores the catalytic efficiencies of structurally similar alpha- and beta-amino acids in an asymmetric aldol transformation. The results show that both types of amino acids achieve high catalytic efficiencies under different optimal conditions, and in some cases, the beta-amino acid even exhibits higher enantioselectivity than the alpha-amino acid.
SYNTHESIS-STUTTGART
(2023)
Article
Chemistry, Physical
Shashikant A. Kadam, Andrew Hwang, Enrique Iglesia
Summary: This study investigates the effects of non-polar liquids on acetone aldol condensation reactions on TiO2 surfaces. The results show that non-polar liquids enhance reaction rates and selectivity by stabilizing transition states for adsorption and desorption. Additionally, solvation by non-polar liquids prevents the formation of larger oligomers, leading to slower deactivation of the catalyst.
Article
Chemistry, Multidisciplinary
Bo-Bo Gou, Yue Tang, Yan-Hong Lin, Le Yu, Qing-Song Jian, Huai-Ri Sun, Jie Chen, Ling Zhou
Summary: A new type of chiral all-carbon tetrasubstituted VQMs was successfully prepared via nucleophilic addition of 2-alkynylnaphthols to o-quinone methides or imines, catalyzed by chiral phosphoric acids. The method showed high efficiency and excellent diastereoselectivities and enantioselectivities, leading to the synthesis of naphthyl-2H-chromenes with axially and centrally chiral elements and axially chiral quinone-naphthols. The obtained axially chiral naphthols could further be converted into valuable phosphine ligands and other functional molecules.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Organic
E. H. Nisala Fernando, Jose Cortes Vazquez, Jacqkis Davis, Weiwei Luo, Vladimir N. Nesterov, Hong Wang
Summary: The formation of enamine from primary arylamines was studied and confirmed, with the necessity of a radical quencher for detection. A direct synthesis of alpha-enaminones from primary arylamines and ketones was developed, and a mechanistic investigation suggested the involvement of an amine radical cation. The reactivity and utility of alpha-enaminones were explored, showing different properties from enamines and advancing understanding in organic chemistry.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Meysam Yarie, Mohammad Ali Zolfigol, Yadollah Bayat, Asiye Asgari, Diego A. Alonso, Abbas Khoshnood
Article
Chemistry, Multidisciplinary
Meysam Yarie, Mohammad Ali Zolfigol, Saeed Baghery, Diego A. Alonso, Abbas Khoshnood, Mehdi Kalhor, Yadollah Bayat, Asiye Asgari
NEW JOURNAL OF CHEMISTRY
(2017)
Article
Chemistry, Multidisciplinary
Diego Ros Niguez, Gabriela Guillena, Diego A. Alonso
ACS SUSTAINABLE CHEMISTRY & ENGINEERING
(2017)
Article
Chemistry, Physical
Melania Gomez-Martinez, Alejandro Baeza, Diego A. Alonso
Article
Chemistry, Multidisciplinary
Maliheh Safaiee, Bahar Ebrahimghasri, Mohammad Ali Zolfigol, Saeed Baghery, Abbas Khoshnood, Diego A. Alonso
NEW JOURNAL OF CHEMISTRY
(2018)
Review
Chemistry, Physical
Diego A. Alonso, Alejandro Baeza, Rafael Chinchilla, Cecilia Gomez, Gabriela Guillena, Isidro M. Pastor, Diego J. Ramon
Article
Chemistry, Physical
Diego Ros Niguez, Pegah Khazaeli, Diego A. Alonso, Gabriela Guillena
Article
Engineering, Chemical
Gabriel Estan-Cerezo, Diego A. Alonso, Jose Miguel Martin-Martinez
JOURNAL OF ADHESION SCIENCE AND TECHNOLOGY
(2019)
Article
Chemistry, Organic
Alberto Martinez-Cuezva, Marta Marin-Luna, Diego A. Alonso, Diego Ros-Niguez, Mateo Alajarin, Jose Berna
Article
Chemistry, Physical
Javad Afsar, Mohammad Ali Zolfigol, Ardeshir Khazaei, Mahmoud Zarei, Yanlong Gu, Diego A. Alonso, Abbas Khoshnood
MOLECULAR CATALYSIS
(2020)
Review
Chemistry, Organic
Diego A. Alonso, Sarah-Jayne Burlingham, Rafael Chinchilla, Gabriela Guillena, Diego J. Ramon, Matteo Tiecco
Summary: This mini-review summarizes recent advances in asymmetric organocatalysis using eutectic mixtures as a reaction medium, as well as the first enantioselective transformations using chiral eutectic solvents. The review aims to delve deep into both the synthetic aspects of asymmetric organocatalysis in eutectic mixtures and the fundamental issues crucial for the successful development of this promising yet challenging methodology.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Jose A. Niguez, Sarah J. Burlingham, Rafael Chinchilla, Diego A. Alonso
Summary: In this study, (S)-(1-Pyrrolidin-2-ylmethyl)quinuclidine-1-ium bromide was synthesized from l-proline in a six-step reaction process and characterized spectroscopically and thermally.
Article
Chemistry, Multidisciplinary
Maria Calles, Julio Puigcerver, Diego A. Alonso, Mateo Alajarin, Alberto Martinez-Cuezva, Jose Berna
Article
Chemistry, Physical
Xavier Marset, Abbas Khoshnood, Lia Sotorrios, Enrique Gomez-Bengoa, Diego A. Alonso, Diego J. Ramon
Article
Chemistry, Physical
Melania Gomez-Martinez, Alejandro Baeza, Diego A. Alonso