C-N bond activation and ring opening of a saturated N heterocyclic carbene via lateral alkali-metal-mediated metallation (AMMM)

Hernán-Gómez, Alberto and Kennedy, Alan and Hevia, Eva (2017) C-N bond activation and ring opening of a saturated N heterocyclic carbene via lateral alkali-metal-mediated metallation (AMMM). Angewandte Chemie International Edition. ISSN 1433-7851 (In Press)

[thumbnail of Hernan-Gomez-etal-ACIE-C-N-bond-activation-and-ring-opening-of-a-saturated-N-heterocyclic-carbene]
Preview
Text. Filename: Hernan_Gomez_etal_ACIE_C_N_bond_activation_and_ring_opening_of_a_saturated_N_heterocyclic_carbene.pdf
Accepted Author Manuscript

Download (1MB)| Preview

Abstract

Combining alkali-metal mediated metalation (AMMM) and N-heterocyclic carbene (NHC) chemistry, a novel C-N bond activation and ring-opening process is described for these increasingly important NHC molecules, which are generally considered robust ancillary ligands. Here, mechanistic investigations on reactions of saturated NHC SIMes (SIMes = [:C{N(2,4,6-Me3C6H2)CH2}2]) with group 1 alkyl bases suggest this destructive process is triggered by lateral metallation of the carbene. Exploiting co-complexation and trans-metal-trapping strategies with lower polarity organometallic reagents (Mg(CH2SiMe3)2 and Al(TMP)iBu2), key intermediates in this process have been isolated and structurally defined.