Role of Group 13 Metals in the Electronic Properties of L(X)M-Substituted Pnictinidenes

Nitrenes are well-established
in organic chemistry as reactive
(intermediate) species, whereas heavier pnictinidenes have only recently
become an emerging class of compounds due to their potential use in
bond activation reactions and catalytic applications. We herein report
on the synthesis of the Al- and In-substituted, carbene-coordinated
pnictinidenes of the general type L(Cl)MPnMecAAC (L = HC[C(Me)N(Dipp)]2, Dipp = 2,6-i-Pr2C6H3; Pn = As, M = Al 1, In 2;
and Pn = Sb, M = Al 3, In 4) by oxidative
addition of monovalent group 13 diyls LM (M = Al, In) to MecAACPnCl. Compounds 1–4 were characterized by heteronuclear nuclear magnetic
resonance spectroscopy (1H and 13C), while their
solid-state structures were determined by single-crystal X-ray diffraction.
Quantum chemical calculations gave a deeper insight into the electronic
nature of pnictinidenes 1–4, and comparison to
previously reported L(Cl)Ga-substituted homologues clearly revealed
the influence of electropositive group 13 metals on their electronic
nature.