Cooperative Bond Activation by a Bimetallic Main-Group Complex

Inspired
by natural metalloenzymes that efficiently catalyze a
variety of transformations, chemists have developed large numbers
of dinuclear transition-metal complexes with extraordinary properties
and reactivity patterns. For main-group element compounds, however,
metal–metal cooperativity is much less explored. Here we present
the synthesis and characterization of a room-temperature-stable compound
with two separated two-coordinated gallium­(I) centers possessing both
a lone pair of electrons and a vacant orbital, reminiscent of singlet
carbenes. This species displays enhanced reactivity compared to its
mononuclear counterpart due to bimetallic cooperativity that allows
for the facile activation of strong C–F bonds across the gallium–gallium
bond. Two mechanistic scenarios of the cooperative bond activation
have been identified by DFT and DLPNO-CCSD­(T) calculations.