Homoleptic LiNacNac forms simple
donor–acceptor complexes
with
N
,
N
′-dicyclohexylcarbodiimide
(CyN=C=NCy), triphenylphosphine oxide (Ph
3
P=O), and benzophenone (Ph
2
CO). These crystallographically
characterized compounds could be regarded as model intermediates en
route to reducing the N=C, P=O, and C=O bonds
of unsaturated substrates. Heteroleptic NacNacMg(TMP) intriguingly
functions as a TMP nucleophile both with
t
-BuNCO
and
t
-BuNCS, producing a urea or thiourea derivative
respectively attached to Mg, though the NacNac ligand in the former
reaction also engages noninnocently with a second
t
-BuNCO molecule via insertion at the reactive NacNac backbone γ-carbon
site.