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Stereoselective Radical C-H Alkylation with Acceptor/Acceptor-Substituted Diazo Reagents via Co(II)-Based Metalloradical Catalysis.

ABSTRACT: Co(II)-based metalloradical catalysis has been, for the first time, successfully applied for asymmetric intramolecular C-H alkylation of acceptor/acceptor-substituted diazo reagents. Through the design and synthesis of a new D2-symmetric chiral amidoporphyrin as the supporting ligand, the Co(II)-based metalloradical system, which operates at room temperature, is capable of 1,5-C-H alkylation of α-methoxycarbonyl-α-diazosulfones with a broad range of electronic properties, providing the 5-membered sulfolane derivatives in high yields with excellent diastereoselectivity and enantioselectivity. In addition to complete chemoselectivity toward allylic and allenic C-H bonds, the Co(II)-based metalloradical catalysis for asymmetric C-H alkylation features a remarkable degree of functional group tolerance.

SUBMITTER: Cui X

PROVIDER: S-EPMC4324598 | biostudies-literature |

REPOSITORIES: biostudies-literature

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