Article
Chemistry, Inorganic & Nuclear
Yafei Li, Huifen Pan, Yanhua Lu, Yanshu Luo, Yan Dang, Yalan Wang, Shengwang Xia, Yahong Li, Yuanzhi Xia
Summary: In order to meet the requirements of environmentally friendly and sustainable chemical processes, researchers have synthesized two lithium and one magnesium complexes and found that they exhibit highly efficient catalytic activity for the hydroboration of aldehydes and ketones.
DALTON TRANSACTIONS
(2022)
Article
Chemistry, Organic
Wei Wang, Shuying He, Yuqing Zhong, Jianhui Chen, Cheng Cai, Yanshu Luo, Yuanzhi Xia
Summary: An efficient cobalt-catalyzed geometrical isomerization of 1,3-dienes is described, where the combination of a CoCl2 precatalyst and anamido-diphosphine-oxazoline ligand enables stereoconvergent conversion of E/Z mixtures of 1,3-dienes to (E) isomers in high stereoselectivity. This method features broad substrate scope, good functional group tolerance, and can be scaled up to gram scale with low catalyst loading.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Sen Lin, Bo Lin, Zongtao Zhang, Jianhui Chen, Yanshu Luo, Yuanzhi Xia
Summary: Using FeCl2 as a catalyst, a facile imidization reaction of phosphines with N-acyloxyamides was conducted at room temperature under air atmosphere, resulting in the formation of N-acyliminophosphoranes. The iminophosphoranyl moiety in the product can be used as an effective directing group for controllable ortho C(sp2)-H bond amidation reactions under Rh(III) catalysis.
Article
Chemistry, Organic
Jinrong Zhang, Jiajia Chen, Jianhui Chen, Yanshu Luo, Yuanzhi Xia
Summary: A convenient photo-dehalogenation method was developed for a-haloketones using irradiation with a purple LED. The reaction could proceed efficiently at room temperature in air atmosphere without the need for a catalyst, with water serving as the sole additive. Mechanistic study revealed that the ether solvent also acted as the photoreductant, and deuterated solvents enabled facile α-deuteration of the ketone products.
TETRAHEDRON LETTERS
(2022)
Article
Chemistry, Multidisciplinary
Siyuan Su, Tongtong Wu, Yuanzhi Xia, Donald J. Wink, Daesung Lee
Summary: The cycloisomerization of alkyne-tethered N-benzoyloxycarbamates to 2-(3H)oxazolones is reported. Two catalytic systems are developed for intramolecular 5-exo-alkyne carboxyamidation and alkene isomerization. PtCl2/CO and FeCl3 are effective catalysts, but FeCl3 requires a cocatalyst for alkene isomerization. A two-step one-pot protocol is established for a broader reaction scope, involving FeCl3-catalyzed carboxyamidation and base-induced alkene isomerization. Crossover experiments suggest the involvement of acylnitrenoid intermediates in these reactions.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Organic
Qiao Li, Yanshu Luo, Jianhui Chen, Yuanzhi Xia
Summary: A catalyst- and metal-free hydrogenation of azobenzenes to hydrazobenzenes in the presence of thioacetic acid was achieved under visible light irradiation. The transformation was carried out under mild conditions in an air atmosphere at ambient temperature, generating a variety of hydrazobenzenes with yields up to 99%. The current process is compatible with a variety of substituents and is highly chemoselective for azo reduction when other unsaturated functionalities (carbonyl, alkenyl, alkynyl, etc.) are contained. Preliminary mechanistic study indicated that the transformation could be a radical process.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Biochemistry & Molecular Biology
Chris Douvris, David Matatov, Derek Bussan, Christos Lampropoulos, Donald J. Wink
Summary: Fluorochemistry is a rapidly advancing field with applications in materials, pharmaceuticals, and agriculture. Synthetic perfluorinated chemistry is particularly underdeveloped in the area of metal complexes, and this study focuses on the synthesis and characterization of a cyclohexadienyl metal complex containing a trifluoromethyl group. The use of Morrison's trifluormethylating reagent resulted in the successful synthesis of the complex, which was characterized using various techniques including X-ray crystallography.
Article
Chemistry, Multidisciplinary
Fa-Jie Chen, Nicole Pinnette, Fan Yang, Jianmin Gao
Summary: In this study, we report a cysteine-directed proximity-driven strategy for constructing bicyclic peptides from simple natural peptide precursors. This linear to bicycle transformation involves rapid cysteine labeling and subsequent amine-selective cyclization. The bicyclization process occurs rapidly under physiological conditions, resulting in bicyclic peptides with Cys-Lys-Cys, Lys-Cys-Lys, or N-terminus-Cys-Cys stapling patterns. We demonstrate the utility and power of this strategy by constructing bicyclic peptides fused to proteins and the M13 phage, enabling the phage display of novel bicyclic peptide libraries.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Laura Alonso, Michael Shevlin, Abdullah S. Alshreimi, Tyler W. Reidl, Donald J. Wink, Laura L. Anderson
Summary: The roles of substituent and solvent effects in promoting the 4p electrocyclization of N-alkenylnitrones to give azetidine nitrones have been investigated. These transformations are synthetically important as they allow for the formation of strained heterocyclic rings with embedded functionality and stereochemical information. Mechanistic investigations, including Hammett studies, solvent-dependent Eyring studies, and solvent isotope effects, provide insights into the factors controlling these electrocyclizations and identify trends for the rapid synthesis of complex azetidines.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
Jacob Jan Markut, Jordi Cabana, Neal P. Mankad, Donald J. Wink
Summary: A symmetry activity using student-built models was developed to engage students in identifying symmetry elements for seven molecules. The activity utilized 2D representations, 3D concrete models, and student-created drawings. The results showed consistent student engagement and increased ability to identify symmetry elements.
JOURNAL OF CHEMICAL EDUCATION
(2023)
Article
Chemistry, Organic
Huiting Wen, Yifei Chen, Lanxuan Shi, Jianhui Chen, Yanshu Luo, Yuanzhi Xia
Summary: An asymmetric hydrosilylation of alpha-oxygenated ketones was developed using Co(OAc)2 as the catalyst in combination with a chiral PAO ligand. This method provides a mild, efficient, and enantioselective access to a variety of synthetically useful 1,2-diol derivatives. The synthetic utility of this protocol was demonstrated by efficient conversion of the optically enriched products into chiral alpha-hydroxy acid, 1,3-dioxolan-2-one, ethylene oxide, and 1,2,3-1H-triazole.
Article
Chemistry, Organic
Risong Wang, Yifei Chen, Binjie Fei, Jiahao Hu, Jianhui Chen, Yanshu Luo, Yuanzhi Xia
Summary: Condition-dependent transformations between hydroximic acids and thioacetic acid were achieved, where NH4HCO3 and ethanol resulted in N-O bond cleavage to afford primary amides, and NEt3 and H2O led to O-acylation. The transformations could be scaled up to the gram level smoothly. Preliminary mechanistic studies suggested a cascade process of acylation/reduction for N-O bond cleavage.
Article
Chemistry, Physical
Bing Li, Yanshu Luo, Min Liu, Yuanzhi Xia, Changkun Li
Summary: The abnormal Claisen rearrangement of phenyl allyl ether with the gamma-alkyl group is well-known, but its asymmetric version has not been reported before. In this study, a highly regio- and enantioselective allylic alkylation of 4-hydroxycoumarin was developed as a formal abnormal Claisen rearrangement. Chiral 4-hydroxycoumarins with 3-allyl groups were synthesized with high yield and enantiomeric excess using rhodium catalyst and chiral bioxazolinephosphine ligand. Experimental and theoretical investigations revealed that the stereospecific rearrangement occurs through the reversible formation of a kinetically favored cis-disubstituted spirocyclopropane intermediate.
Article
Chemistry, Organic
Junjie Ying, Jingrong Huang, Chenguang Liu, Fa-Jie Chen, Chunfa Xu, Fen-Er Chen
Summary: This study reports a copper-catalyzed arylation reaction using readily available arylboronic acids for S-tosyl peptides. The method features high yields and a wide variety of aryl groups, enabling efficient synthesis of S-arylated cysteines and peptides under mild conditions.
ORGANIC CHEMISTRY FRONTIERS
(2023)
