Hydrogen chloride solution (1.0 M in diethyl ether) is generally prepared by passing HCl gas through diethyl ether solvent. It is suitable for air/moisture-sensitive reactions.

Hydrogen chloride solution (1.0 M in diethyl ether) can be used in the synthesis of molybdenum adamantylimido and t-butylimido alkylidene chloride complexes in the presence of PPh₂Me. It is also used in some cyclization reactions, for example, in the cyclization of oxadiazole derivatives from corresponding thiosemicarbazides.