Chromium(II)-Catalyzed Diastereoselective and Chemoselective Csp(2)-Csp(3) Cross-Couplings Using Organomagnesium Reagents

Li, Jie; Ren, Qianyi; Cheng, Xinyi; Karaghiosoff, Konstantin and Knochel, Paul (2019): Chromium(II)-Catalyzed Diastereoselective and Chemoselective Csp(2)-Csp(3) Cross-Couplings Using Organomagnesium Reagents. In: Journal of the American Chemical Society, Vol. 141, No. 45: pp. 18127-18135

Abstract

A simple protocol for performing chromium catalyzed highly diastereoselective alkylations of arylmagnesium halides with cyclohexyl iodides at ambient temperature has been developed. Furthermore, this ligand-free CrCl2 enables efficient electrophilic alkenylations of primary, secondary, and tetiary alkylmagnesium halides with readily available alkenyl acetates. Moreover, this chemoselective C-C coupling reaction with stereodefined alkenyl acetates proceeds in a stereoretentive fashion. A wide range of functional groups on alkyl iodides and alkenyl acetates are well tolerated, thus furnishing functionalized Csp(2)-Csp(3) coupling products in good yields and high diastereoselectivity. Detailed mechanistic studies suggest that the in situ generated low-valent chromium(I) species might be the active catalyst for these Csp(2)-Csp(3) cross-couplings.

• Item Type: Journal article
• Faculties: Chemistry and Pharmacy > Department of Chemistry
• Subjects: 500 Science > 540 Chemistry
• ISSN: 0002-7863
• Language: English