Highly Soluble Cyclic Organoalanes Based on Anionic Dicarbenes

Abstract

AbstractCyclic organoalane compounds [(ADCAr)AlH2]2 (ADCAr = ArC{(DippN)C}2; Dipp = 2,6‐iPr2C6H3; Ar = Ph or 4‐PhC6H4 (Bp)) based on anionic dicarbene (ADC) frameworks have been reported as crystalline solids. Treatments of Li(ADCAr) with LiAlH4 at room temperature afford [(ADCAr)AlH2]2 with the concomitant release of LiH. Compounds [(ADCAr)AlH2]2 are stable crystalline solids and are freely soluble in common organic solvents. They are annulated tricyclic compounds with an almost planar central C4Al2‐core embedded between two peripheral 1,3‐imidazole (C3N2) rings. At room temperature, [(ADCPh)AlH2]2 readily reacts with CO2 to form two‐ and four‐fold hydroalumination products [(ADCPh)AlH(OCHO)]2 and [(ADCPh)Al(OCHO)2]2, respectively. Further hydroalumination reactivity of [(ADCPh)AlH2]2 has been shown with isocyanate (RNCO) and isothiocyanate (RNCS) species (R=alkyl or aryl group). All compounds have been characterized by NMR spectroscopy, mass spectrometry, and single‐crystal X‐ray diffraction.