Copper-catalyzed fluoroamide-directed remote benzylic C-H olefination: facile access to internal alkenes

作者：Zhong, Long-Jin; Lv, Gui-Fen^*; Ouyang, Xuan-Hui; Li, Yang^*; Li, Jin-Heng^*

来源：Organic Chemistry Frontiers, 2022, 9(16): 4309-4315.

DOI：10.1039/d2qo00822j

• C(SP(3))-H BONDS
• FUNCTIONALIZATION
• PHOTOREDOX
• ALKYLATION
• DESATURATION
• CYANATION
• RADICALS
• AMINES

The general, site-selective copper-catalyzed fluoroamide-directed remote benzylic C-H olefination of N-fluoroamides with terminal alkenes for producing internal alkenes is disclosed. This protocol proceeds via a hybrid Cu-radical mechanism, which synergistically combines the favorable features of radical transformations (such as a site-selective remote C-H hydrogen atom transfer (HAT) step) with those of transition-metal catalysis (such as a selective beta-hydrogen elimination step). The cooperative Cu and dinitrogen-based ligand catalytic systems are crucial, as they not only preferentially enable the coupling of terminal alkenes with remote benzylic C-H bonds through the chemoselective recognition of two remote delta-C(sp(3))-H bonds respectively existing in two distinct alkyl-based chains linked to the nitrogen atom of the N-fluoroamides, but they also precisely control site selectivity for the olefination of remote benzylic C-H bonds in a delta position relative to the amidyl nitrogen atom.

• 单位
  云南大学; 南昌航空大学; y; 兰州大学