The invention discloses a preparation method of a beta
receptor blocker crude product, which comprises the following steps: (1) adding [(S)-2, 2-dimethyl-1, 3-
dioxolane-4-yl] methyl-3-[4-[(S)-2-hydroxy-3-(2-
morpholine formylamino) ethylamino] propoxy] phenylpropionate into a
solvent, and reacting with
oxalic acid to generate [(S)-2, 2-dimethyl-1, 3-
dioxolane-4-yl] methyl-3-[4-[(S)-2-hydroxy-3-(2-
morpholine formylamino) ethylamino] propoxy] phenylpropionate; the preparation method comprises the following steps: preparing 1, 3-
dioxolane-4-yl] methyl-3-[4-[(S)-2-hydroxy-3-(2-
morpholine formylamino) ethylamino] propoxy] phenylpropionate
oxalate; (2) dissolving the [(S)-2, 2-dimethyl-1, 3-dioxolane-4-yl] methyl-3-[4-[(S)-2-hydroxy-3-(2-morpholine formylamino) ethylamino] propoxy] phenylpropionate
oxalate obtained in the step (1), and then forming a beta
receptor blocker with a
hydrogen chloride and
ethyl acetate solution by using the dissolved [(S)-2, 2-dimethyl-1, 3-dioxolane-4-yl] methyl-3-[4-[(S)-2-hydroxy-3-(2-morpholine formylamino) ethylamino] propoxy] phenylpropionate
oxalate and the
hydrogen chloride and
ethyl acetate solution; wherein the
oxalic acid is
oxalic acid dihydrate. The beta
receptor blocker crude product obtained in the invention has relatively high purity and yield.