Mesoionic Dithiolates (MIDts) Derived from 1,3‐Imidazole‐Based Anionic Dicarbenes (ADCs)
Falk Ebeler, Yury V. Vishnevskiy, Beate Neumann, Hans‐Georg Stammler, Rajendra S. Ghadwal
Abstract
Abstract Mesoionic dithiolates [(MIDt Ar )Li(LiBr) 2 (THF) 3 ] (MIDt Ar ={SC(NDipp)} 2 CAr; Dipp=2,6‐ i Pr 2 C 6 H 3 ; Ar=Ph 3 a , 3‐MeC 6 H 4 (3‐Tol) 3 b , 4‐Me 2 NC 6 H 4 (DMP) 3 c ) and [(MIDt Ph )Li(THF) 2 ] ( 4 ) are readily accessible (in≥90 % yields) as crystalline solids on treatments of anionic dicarbenes Li(ADC Ar ) ( 2 a ‐ c ) (ADC Ar ={C(NDipp) 2 } 2 CAr) with elemental sulfur. 3 a ‐ c and 4 are monoanionic ditopic ligands with both the sulfur atoms formally negatively charged, while the 1,3‐imidazole unit bears a formal positive charge. Treatment of 4 with (L)GeCl 2 (L=1,4‐dioxane) affords the germylene (MIDt Ph )GeCl ( 5 ) featuring a three‐coordinated Ge atom. 5 reacts with (L)GeCl 2 to give the Ge−Ge catenation product (MIDt Ph )GeGeCl 3 ( 6 ). KC 8 reduction of 5 yields the homoleptic germylene (MIDt Ph ) 2 Ge ( 7 ). Compounds 3 a ‐ c and 4 – 7 have been characterized by spectroscopic studies and single‐crystal X‐ray diffraction. The electronic structures of 4 – 7 have been analyzed by DFT calculations.