Article
Chemistry, Organic
Pedro P. De Castro, Gabriel M. F. Batista, Giovanni W. Amarante, Helio F. Dos Santos
Summary: Theoretical calculations and control experiments were used to investigate the mechanism and origin of enantioselectivity in the phosphoric-acid-catalyzed dynamic kinetic resolution of azlactones. The results identified a Munchnone intermediate as crucial in the isomerization of azlactone rings, and the developed model successfully predicted enantioselectivity under various reaction conditions.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Patrick S. Fier, Riley A. Roberts, Reed T. Larson
Summary: We have developed a method for converting esters to ketones in a single step using simple reagents. This selective transformation is achieved by activating the adjacent carbon to deprotonation through the use of a transient sulfinate group on the nucleophile, allowing the formation of a carbanion that adds to the ester. This reaction is then followed by another deprotonation step to prevent further addition, and the resulting dianion spontaneously fragments the SO2 group upon quenching with water to produce the ketone product.
Article
Chemistry, Organic
Han Hao, Thibault Bagnol, Mathieu Pucheault, Laurel L. Schafer
Summary: By utilizing a specific titanium precatalyst, the hydroamination of alkynylphosphines to prepare 2-amino-phosphines in high yield and on gram scale has been achieved. The broad substrate scope allows for the rapid assembly of a variety of ligands in one pot, making preparation of metal P,N-complexes for catalysis or small molecule activation easy and efficient.
Review
Chemistry, Multidisciplinary
Oleksandr Vyhivskyi, Anton Kudashev, Takeru Miyakoshi, Olivier Baudoin
Summary: Processes involving transition-metal catalysis have become a major part of synthetic chemists' toolbox in recent decades. The focus has shifted from cross-coupling reactions to C-H bond functionalization, with constant progress leading to discovery of enantioselective methods. The review discusses enantioselective Pd-0-catalyzed C-H activation, highlighting the importance of different chiral ligands and catalysts in enabling these transformations.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Chemistry, Multidisciplinary
Lingpu Meng, Jingjie Yang, Mei Duan, You Wang, Shaolin Zhu
Summary: Regio- and enantioselective hydroarylamination, hydroalkylamination and hydroamidation of styrenes have been developed using NiH catalysis with a simple bioxazoline ligand under mild conditions. A variety of enantioenriched benzylic arylamines, alkylamines and amides can be easily accessed by employing nitroarenes, hydroxylamines and dioxazolones as amination reagents. Chiral induction in these reactions is proposed to proceed through an enantiodifferentiating syn-hydronickellation step.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Organic
Ayushee, Monika Patel, Priyanka Meena, Kousar Jahan, Prasad Bharatam, Akhilesh K. Verma
Summary: A base-promoted protocol was investigated for the intermolecular anti-Markovnikov hydroamidation of vinyl arenes, leading to the formation of arylethylbenzamides with excellent chemo- and regioselectivity. The reaction demonstrated high chemoselectivity for the amide group over amine and tolerance towards a wide variety of functional groups. The proposed mechanism and the importance of the solvent were supported by deuterium labeling studies and control experiments.
Article
Chemistry, Organic
Wanlong Xiao, Fang Li, Xiaohua Liu, Weidi Cao, Xiaoming Feng
Summary: A catalytic asymmetric tandem cyclization of azadienes and ortho-alkynylnaphthols accelerated by a chiral N,N'-dioxide-gadolinium(III) complex is reported. This method allows the synthesis of 1,2-dihydrobenzofuro[3,2-b]pyridines containing both axially and centrally chiral elements in high yields and excellent stereoselectivities.
Article
Chemistry, Physical
Zeng Gao, Chao-Xian Yan, Jinlong Qian, Huameng Yang, Panpan Zhou, Jinlong Zhang, Gaoxi Jiang
Summary: An efficient and rapid method for constructing a family of axially chiral sulfonamides with a wide functional group tolerance has been developed through Pd-catalyzed atroposelective hydroamination. Simple oxidation and gamma-addition enabled the synthesis of various valuable axially chiral sulfonamides and anilides, including non-natural amino acid derivatives. Preliminary DFT calculations were used to explain the origin of asymmetric induction.
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)
Review
Chemistry, Multidisciplinary
Josep Mas-Rosello, Ana G. Herraiz, Benoit Audic, Aragorn Laverny, Nicolai Cramer
Summary: The development of new chiral ligands is crucial for stereocontrol in metal-catalyzed reactions, especially with the increasing demand for bioactive molecules as single enantiomers. The successful application of Cp-X ligands in metal-catalyzed transformations allows access to valuable chiral molecules, with critical comparisons of existing ligand families and discussion of future research directions for further enhancing their performance and application in enantioselective catalysis.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Physical
Philipp S. Steinlandt, Xiulan Xie, Sergei Ivlev, Eric Meggers
Summary: A class of stereogenic-at-iron catalysts has been introduced for asymmetric 3d-transition metal catalysis. These catalysts have shown high yield and high enantioselectivity. The coordination and dynamics of the ligands were studied using NMR spectroscopy.
Article
Chemistry, Multidisciplinary
Xiaoqiang Yan, Jijun Jiang, Jun Wang
Summary: In this study, an unusual class of planar-chiral rhodium catalysts bearing non-chiral Cp ligands was described. These catalysts are readily tunable and were successfully used in enantioselective C-H activation reactions, showing great potential in this field.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Physical
Neha Antil, Naved Akhtar, Rajashree Newar, Wahida Begum, Ajay Kumar, Manav Chauhan, Kuntal Manna
Summary: The development of efficient and enantioselective heterogeneous catalysts based on abundant elements and inexpensive ligands is crucial for environmentally friendly and cost-effective production of optically active compounds. This study demonstrates the synthesis of chiral amino alcohol-functionalized metal-organic frameworks as highly enantioselective base-metal catalysts for asymmetric organic transformations.
Article
Chemistry, Organic
Shibo Yu, Qihang Cai, Tianxu Yu, Jiahui Li, Chao Yao, Yue-Ming Li
Summary: This paper describes the design and application of new chiral ligands based on binaphthyl and proline skeletons, which incorporate regulatable electronic and steric properties for the imidazoline functional groups. These ligands form chiral complexes with different metal salts and can be used as catalysts for enantioselective conjugate addition reactions, resulting in high yields and excellent enantiomeric excess.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Jia-Feng Chen, Sajid Ur Rehman, Changkun Li
Summary: A regiodivergent cobalt-catalyzed addition of nucleophiles to allenes has been developed, providing substituted enol esters and branched-allylic products in high yields and with unique selectivities, indicating the distinct reactivity of cobalt compared to rhodium and iridium in allene hydrofunctionalization.
ORGANIC CHEMISTRY FRONTIERS
(2022)