Toward asymmetric aziridination with an iron complex supported by a D₂-symmetric tetra-NHC

Abstract

A macrocyclic C2-symmetric tetra-NHC iron(ii) complex was synthesized and tested for asymmetric aziridination between aryl azides and alkenes.

Catalytic Nitrene Transfer by an FeIV‐Imido Complex Generated by a Comproportionation Process

“…(See ligands depicted in Scheme S2). [25,[35][36][37] Jenkins and coll. showed that these systems exhibit interesting nitrene transfer activities but need to operate at temperatures ca.…”

“…Pursuing our quest for efficient aziridination catalysts, our attention was attracted by the Fe complexes of tetracarbene macrocyclic ligands reported by the groups of Jenkins, Kühn and Meyer. (See ligands depicted in Scheme S2) [25,35–37] . Jenkins and coll.…”

Cyclic iron tetra N-heterocyclic carbenes: synthesis, properties, reactivity, and catalysis

“…70 The obtained silver complexes can subsequently be treated with an iron halide and the formed silver halide be removed by filtration over Celite to receive the respective iron complexes. 69,70…”

“…Generally speaking, it has to be pointed out, that the aziridination of alkenes with organic azides at these conditions already proceeds without an iron complex in low (2%) up to moderate yields (60%). 64,65,69,103,235,236 In extreme cases, this can make Scheme 32 Aziridination of olefins with organic azides catalyzed by 8, 16, 17 and 62.…”

The first macrocyclic abnormally coordinating tetra-1,2,3-triazole-5-ylidene iron complex: a promising candidate for olefin epoxidation

“…11 Tuning of its electronic properties by insertion of substituents varying the NHC backbone affects not only catalyst stability but also its activity, emphasising once more the role of ligand design. 12 Pioneering work on bio-inspired non-heme macrocyclic iron tetra(NHCs) has been done by Jenkins et al [13][14][15][16][17][18] , Meyer et al [19][20][21] and our group. 12,[22][23][24][25][26] During these studies several bridged tetra(imidazole-2-ylidene) iron complexes have been prepared and characterised (Fig.…”