Cyclopropyl groups are widely found in pharmaceutical products and their application as precursors or key reaction intermediates benefits the development of a wide range of reactions. Herein, we report a facile protocol for the synthesis of this compound through gold-catalyzed [2 + 1] cycloaddition of allenamides with sulfoxonium ylides. The reaction exhibited good functional group tolerance and high efficiency, affording the products in good to excellent yields with good diastereoisomerism. The steric hindrance between the sulfonamide group and the gold catalyst determined the major configuration of the formed -cyclopropane product. Moreover, the aldehyde could be converted to amide under Schmidt reaction conditions and alcohol under reduction conditions.
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http://dx.doi.org/10.1039/d3ob00390f | DOI Listing |
iScience
October 2024
Department of Chemistry, State Key Laboratory of Synthetic Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong 999077, China.
Gold(I)-catalyzed highly enantioselective [4 + 2] cycloadditions of 1,6-enynes were achieved by utilizing chiral bifunctional P,N ligand. A wide range of 1,6-enynes were converted to enantioenriched 5-6-6-fused tricyclic compounds under mild reaction condition (up to 99% ee). This chiral gold(I) complex was also employed in the first desymmetric cycloadditions of 1,6-diynes bearing single ester group at the tether (up to 93% ee), where 5-- pathway predominates over 6-- pathway.
View Article and Find Full Text PDFOrg Lett
August 2024
Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai - 400076, India.
Gold-catalyzed 5- hydroamination on -homopropargylic hydroxylamine gave expeditious access to methylene isoxazolidine. Excess catalyst loading led to facile 1,3-sulfonyl migration in a cascade fashion to furnish the isoxazoline. Mechanistic studies using react-IR and NMR as well as crossover experiments indicated that 1,3-sulfonyl group migration is an intramolecular concerted process.
View Article and Find Full Text PDFOrg Lett
July 2024
State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032, People's Republic of China.
A gold-catalyzed cycloaddition/ring opening of allenamides with quinoline -oxides has been developed, which provides C2-alkenylated quinolines with high selectivity in moderate to high yields. It is noted that quinoline -oxides with a C8 or C7 substituent are crucial for this catalytic reaction.
View Article and Find Full Text PDFChem Sci
June 2024
Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), NMPA Key Laboratory for Technology Research and Evaluation of Drug Products, School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University Jinan Shandong 250012 China
Chiral eight-membered heterocycles comprise a diverse array of natural products and bioactive compounds, yet accessing them poses significant challenges. Here we report a gold-catalyzed stereoselective (4 + 4) cycloaddition as a reliable and divergent strategy, enabling readily accessible precursors (anthranils and -quinone methides) to be intercepted by generated gold-furyl 1,4-dipoles, delivering previously inaccessible chiral furan/pyrrole-containing eight-membered heterocycles with good results (56 examples, all >20 : 1 dr, up to 99% ee). Moreover, we achieve a remarkably efficient kinetic resolution (KR) process (s factor up to 747).
View Article and Find Full Text PDFNat Prod Rep
July 2024
Key Laboratory of Bioorganic Chemistry and Molecular Engineering, Ministry of Education, Beijing National Laboratory for Molecular Science, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China.
Covering: 2016 to mid 2023Transition metal catalysis, known for its remarkable capacity to expedite the assembly of molecular complexity from readily available starting materials in a single operation, occupies a central position in contemporary chemical synthesis. Within this landscape, gold-catalyzed reactions present a novel and versatile paradigm, offering robust frameworks for accessing diverse structural motifs. In this review, we highlighted a curated selection of publications in the past 8 years, focusing on the deployment of homogeneous gold catalysis in the ring-forming step for the total synthesis of natural products.
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