“…chloride can be minimized by the following techniques : (a) passage of an inert gas through the mixture [7, 8a, b], (b) use of reduced pressure to remove hydro gen chloride [9], (c) use of a solvent in which hydrogen chloride is insoluble (CH 2 C1 2 , CHC1 3 , CCI4, C 6 H 5 C1, and o-C 6 H 4 Cl 2 ) [10], or (d) use of a tertiary amine (triethylamine, pyridine, or quinoline) as a hydrogen chloride scavenger [11]. Gerrard [11] had shown earlier that the slow addition of 0.5 mole of thionyl chloride to a mixture of pyridine (1.0 mole) and hydroxy compounds («-butyl, H-amyl, or ethyl lactate-0.1 mole) gives pyridine hydrochloride and good yields of the sulfite (see Eq.…”