Starting from [Al(DMP)Cl2], which was synthesized according to the procedure described by Mai et al. , 1 and 2 were prepared via salt-metathesis reaction with one or two equivalents of LiH, respectively. While the reactants for 1 were employed as solids and dissolved in Et2O at -50 °C, for the synthesis of 2 a slurry of LiH in Et2O was added to a solution of [Al(DMP)Cl2] in Et2O via cannula. Work-up of the crude products was done via sublimation for the solid compound 1, and via distillation in case of 2. Crystals of 1 suitable for SCXRD could be picked directly from the sublimation finger after work-up, confirming and refining the previously reported structure of Dümichen et al. Crystallographic data are given in the supplementary information (table_SI 1, table_SI 2 and figure_SI 1). Compound 2 is being isolated for the first time and it is a highly reactive liquid at room temperature, slightly fuming at O2 concentrations as low as 15 ppm, presumably under HCl elimination, and solidifies amorphous at -30 °C. Thus, no suitable crystals of 2 could be isolated for SCXRD. However, the liquid aggregation is favored for the application as precursor, ensuring constant surface for evaporation. It is also worth Synthesis of 3 was done by treating 2 with a stoichiometric amount of methyl lithium (MeLi) at -80 °C. It should be noted that the stability of 3 is significantly lower than for the analogues 1 and 2, resulting in rather limited proof for distinct compound characterization. Work-up via distillation of the liquid crude product of 3 resulted in decomposition, which also takes place upon dissolution in dried and degassed NMR solvents (C6D6, CDCl3). Thus, compound formation can only be assumed and supported by FTIR (ν(Al-H) = 1690 cm -1 ) as well as H NMR spectroscopy showing a mixture of 3 and its decomposition product. Considering the targeted application and the prerequisite in terms of thermal stability, further attempts to isolate, and characterize this compound were not undertaken. Attempts to synthesize the amide analogue [Al(DMP)(NMe2)H] by treatment of 2 with one equivalent of lithium dimethyl amide were not successful.