A Digermanium(III) 1,2-Dication Stabilized by Amidinate and cAAC-Phosphinidenide Ligands.

A digermanium(III) 1,2-dication comprises two cationic centers located at two interconnected Ge atoms. The strong Coulombic repulsion between two positively charged germanium cations hinders their bond formation. Balancing these two oppositions was achieved by using amidinate and cyclic (alkyl)amino carbene (cAAC)-phosphinidenide ligands, where an amidinato cAAC-phosphinidenidogermylene complex, [LGeP(cAAC Me )] ( 2 , where L = PhC(N t Bu) 2 , cAAC Me = :C{C(Me) 2 CH 2 C(Me) 2 NAr}, and Ar = 2,6- i Pr 2 C 6 H 3 ), underwent one-electron oxidation with a bis(phosphinidene) radical cation, [(cAAC Me )P] 2 •+ , to form a digermanium(III) 1,2-dication, [LGeP(cAAC Me )] 2 2+ , in compound 4 .