Proxodolol (V) was obtained as shown in Scheme 21696501a: Monoalkylation of pyrocatechol with chloroacetic acid gives 2-hydroxyphenoxyacetic acid (I), which is cyclized on heating into 1,4-benzodioxan-2-one (II). Condensation of (II) with acetamidoxime, giving 2-methyl-5-(2-hydroxyphenoxymethyl)-1,2,4-oxadiazole (III), followed by alkylation with epichlorohydrin yields the corresponding diether (IV), which smoothly reacts with tert-BuNH2, and the amine (V) is converted into its hydrochloride by reaction with HCl.

Proxodolol (V) was obtained as shown in Scheme 21696501a: Monoalkylation of pyrocatechol with chloroacetic acid gives 2-hydroxyphenoxyacetic acid (I), which is cyclized on heating into 1,4-benzodioxan-2-one (II). Condensation of (II) with acetamidoxime, giving 2-methyl-5-(2-hydroxyphenoxymethyl)-1,2,4-oxadiazole (III), followed by alkylation with epichlorohydrin yields the corresponding diether (IV), which smoothly reacts with tert-BuNH2, and the amine (V) is converted into its hydrochloride by reaction with HCl.

Proxodolol (V) was obtained as shown in Scheme 21696501a: Monoalkylation of pyrocatechol with chloroacetic acid gives 2-hydroxyphenoxyacetic acid (I), which is cyclized on heating into 1,4-benzodioxan-2-one (II). Condensation of (II) with acetamidoxime, giving 2-methyl-5-(2-hydroxyphenoxymethyl)-1,2,4-oxadiazole (III), followed by alkylation with epichlorohydrin yields the corresponding diether (IV), which smoothly reacts with tert-BuNH2, and the amine (V) is converted into its hydrochloride by reaction with HCl.