Copper-Mediated N‑Arylations of Hydantoins

A set of two broadly
applicable procedures for the N-arylation
of hydantoins is reported. The first one relies on the use of stoichiometric
copper­(I) oxide under ligand- and base-free conditions and enables
a clean regioselective arylation at the N3 nitrogen atom,
while the second one is based on the use of catalytic copper­(I) iodide
and trans-N,N′-dimethylcyclohexane-1,2-diamine
and promotes arylation at the N1 nitrogen atom. Importantly,
the combination of these two procedures affords a straightforward
entry to diarylated hydantoins.