LDA is commonly formed by treating a cooled (0 to −78 °C) mixture of tetrahydrofuran and diisopropylamine with n-butyllithium.
When dissociated, the diisopropylamide anion can become protonated to form diisopropylamine. Diisopropylamine has a pK value of 36. Therefore, its conjugate base is suitable for the deprotonation of compounds with greater acidity, importantly, such weakly acidic compounds (carbon acids) of the type , where Z = C(O)R, C(O)OR or CN. Conventional protic functional groups such as alcohols and carboxylic acids are readily deprotonated.
Like most organolithium reagents, LDA is not a salt, but is highly polar. It forms aggregates in solution, with the extent of aggregation depending on the nature of the solvent. In THF its structure is primarily that of a solvated dimer. In nonpolar solvents such as toluene, it forms a temperature-dependent oligomer equilibrium. At room temperature trimers and tetramers are the most likely structures. With decreasing temperature the aggregation extends to pentameric and higher oligomeric structures.
Solid LDA is pyrophoric, but its solutions are generally not. As such it is commercially available as a solution in polar aprotic solvents such as THF and ether; however, for small scale use (less than 50 mmol), it is common and more cost effective to prepare LDA in situ.