Tripodal S‑Ligand Complexes of Copper(I) as Catalysts for Alkene Aziridination, Sulfide Sulfimidation, and C–H Amination

Copper­(I) complexes
of tris­(thioimidazolyl)­borates (R′TmR), including
[Cu­(TmPh)­(PR″3)] (R″ = Ph, Cu1; Cy, Cu2) and [Cu­(R′TmPh)­(PR″3)]+ (R′ = N-methylimidazole; R″ = Ph, Cy) were prepared and characterized
by spectroscopic methods. The X-ray crystal structures of Cu1 and Cu2 feature a tripodal TmPh ligand coordinated
in κ3-S,S,S mode. Using Cu2 as a catalyst
(loading: 1 mol %), the aziridination of styrenes and sulfimidation
of thioanisoles with PhINTs at RT for 3 and 0.5 h, respectively,
both resulted in product yields of up to 99%. Cu2 also
catalyzed intramolecular amination of the aryl C–H bond of
vinyl azides with up to 98% yield. DFT calculations were performed
to gain insight into the mechanism of the Cu2-catalyzed
aziridination reaction.