PUB - Publikationen an der Universität Bielefeld

Double deprotonations of the C2-arylated 1,3-imidazolium salts (IPr-Ar)X (1-Ar)X (IPr-Ar = ArC{N(Dipp)CH}2; Ar = Ph, 4-Me2NC6H4 (DMP) or 4-PhC6H4 (Bp); Dipp = 2,6-iPr2C6H3) with nBuLi afford the so-called anionic dicarbenes Li(ADC) (2-Ar) (ADC = ArC{N(Dipp)C}2). 2-Ar can be used to prepare a variety of main group heterocycles, however their structures in the solid-state remained hitherto unknown. Herein reported single-crystal X-ray diffraction studies reveal an acetylide type [ArC{N(Dipp)}(Dipp)NC=CLi)]n (3-Ar) dimeric (n = 2) or trimeric (n = 3) molecular structure for 2-Ar. Treatment of 3-Ar with Et3B cleanly yields the monoanionic carbene Li[(ADC)(BEt3)] (4-Ar) featuring a weakly coordinating anion embedded in the same molecular entity. 3-Ar readily undergoes reactions with CO2 and N2O to form the ring-closing products Li[(ADC)(CO2)2] (5-Ar) and Li[(ADC)N2O] (6-Ar), respectively. © 2025 Wiley‐VCH GmbH.