N-Heterocyclic imine-based bis-gallium(i) carbene analogs featuring a four-membered Ga₂N₂ ring

A combination of Ga(i) centers as important building blocks and scaffolds containing N-heterocyclic imines gives new insights into low-valent Ga chemistry. In this study, a mixture of (LNLi)-N-Dip (L-Dip = 1,3-bis(2,6-diisopropylphenyl)-imidazolin-2-ylidene), (BuOK)-Bu-t, and Cp*Ga (Cp* = pentamethylcyclopentadienyl) in toluene afforded [(LN)-N-Dip-Ga](2) (1) via salt metathesis. X-ray structure analysis of 1 revealed a four-membered Ga2N2 ring, and DFT studies indicated the presence of a lone pair at each Ga center. In addition, compound 1 demonstrated diverse reactivities towards methyl trifluoromethanesulfonate, diphenyl disulfide, 9,10-phenanthrenequinone, and ECl2 (E = Ge or Sn).