A new method for the cross-coupling reaction of Grignard reagents with alkyl chlorides, bromides, and tosylates has been developed by the use of a nickel catalyst in the presence of a diene as an additive. This reaction proceeds efficiently at 0-25 degrees C in THF using primary and secondary alkyl and aryl Grignard reagents. Nickel complexes bearing no phosphine ligands, such as NiCl2, Ni(acac)2, and Ni(COD)2, afford the coupling products in good yields, whereas NiCl2(PPh3)2 and NiCl2(dppp) were less effective. 1,3-Butadiene shows the highest activity as an additive for the present coupling reaction. A plausible reaction pathway was proposed.
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http://dx.doi.org/10.1021/ja025828v | DOI Listing |
Org Lett
January 2025
The Zhongzhou Laboratory for Integrative Biology, State Key Laboratory of Antiviral Drugs, School of Pharmacy, Henan University, Kaifeng, Henan 475004, China.
A novel strategy is reported for the stereoselective synthesis of C(sp)-C(sp) -glycosides, which converts heteroaryl -glycosides into heteroaryl -glycosides with retention of configuration through a sequential process involving oxidation and Grignard reagent attack. The new method involves the generation of a S(IV) intermediate, followed by ligand coupling of the glycosyl and heteroaryl groups to yield heteroaryl -glycosides. The diverse heteroaryl -glycosides were achieved with good efficiency.
View Article and Find Full Text PDFChem Commun (Camb)
January 2025
Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, Stockholm, SE-10691, Sweden.
Herein, we present a highly efficient allylic substitution of carbonates with Grignard reagents using a reusable cellulose-supported nanocopper catalyst. This approach highlights the first instance of heterogeneous catalysis for the cross-coupling of allylic alcohol substrates with Grignard reagents. The method features high yields, excellent regioselectivity, and complete chirality transfer.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
Osaka University: Osaka Daigaku, Department of Applied Chemistry, JAPAN.
Although numerous transition-metal catalyzed cross-coupling reactions of alkenyl electrophiles with a sulfur(VI) leaving group, mainly alkenyl sulfones, have been developed, most rely heavily on highly nucleophilic Grignard reagents, and the use of organoboron reagents remains challenging. We report herein facile preparation and the following Pd-catalyzed Suzuki-Miyaura cross-coupling reaction of alkenyl sulfoximine, a monoaza analog of sulfone. The condensation of alkyl sulfoximine with aldehydes, developed in this study, makes alkenyl sulfoximines more readily available.
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January 2025
College of Chemistry, Zhengzhou University, Zhengzhou, Henan 450001, China.
Herein, we report a method for the regioselective alkylation and phosphonation of quinoline C4-H via a BH-mediated nucleophilic addition of Turbo Grignard reagents and phosphine oxide anions to quinolines bearing different substituents, affording the 4-alkyl and 4-phosphoryl quinolines and tetrahydroquinolines after one-pot oxidation or reduction. The results indicate that coordination of the BH group can activate substrates toward a potential 1,4-dearomative addition and subtly control the regioselectivity by preventing the 1,2-dearomative addition.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
December 2024
Department of Chemistry, Faculty of Science, National University of Singapore, 3 Science Drive 2, Singapore, 117543, Singapore.
Asymmetric synthesis relies on seamless transmission of stereochemical information from a chiral reagent/catalyst to a prochiral substrate. The disruption by substrates' structural changes presents a hurdle in innovating generality-oriented asymmetric catalysis. Here, we report a strategy for substrate adaptability by exploiting a fundamental physicochemical phenomenon-ion hydration, in developing remote desymmetrization to access P-stereogenic triarylphosphine oxides and sulfides.
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