The absence of residual solvent in metal precursors can be of key importance for the successful preparation of metal complexes or materials. Herein, we describe methods for the quantitation of residual coordinated tetrahydrofuran (THF) that binds to Fe[N(SiMe3)(2)](2), a commonly used iron synthon, when prepared according to common literature procedures. A simple method for quantitation of the amount of residual coordinated THF using H-1 NMR spectroscopy is highlighted. Finally, a detailed synthetic procedure is described for the synthesis of THF-free Fe[N(SiMe3)(2)](2).