Improved process for the preparation of propargyl ammonium-chloride derivatives

摘要

Method for the prepn. of L-isomers of propargyl ammonium chloride derivs. of formula (I) involves: (a) treatment of the D-tartrate of the L-isomer of a secondary amine with an aq. soln. of NH4OH or basic alkaline salt and/or ammonium salt to release the amine (II); (b) reaction with 1-1.5 mol. equivs. of a propargyl halide (V) at 0-50 [deg]C at pH 8-12 to give the alkylated free base (III); (c) treatment with aq. NH4OH and/or aq. phosphate salt of pH 5.5-7.5 to remove unreacted (II) and other impurities; (d) distillation of the organic layer to obtain pure (III); and (e) conversion of (III) to the HCl salt (I): X = halo; and Y = H or F.