The chloromethylation of 4-hydroxyacetophenone (V) with formaldehyde and HCl in hot water gives 3-chloromethyl-4-hydroxyacetophenone (VI), which is treated with acetic anhydride-sodium acetate in refluxing acetic acid to afford 3-acetoxymethyl-4-acetoxyacetophenone (VII). The bromination of (VII) with Br2 in chloroform yields after hydrolysis 3-hydroxymethyl-4-hydroxyphenacyl bromide (VIII), which is condensed with benzyl tert-butylamine (II) in refluxing benzene giving alpha-(N-benzyl-N-tert-butylamino)-4-hydroxy-3-hydroxymethylacetophenone (IX). Finally, this compound is hydrogenated with H2 over Pd/C in ethanol. An alternative method of hydrogenation of (IX) is its reduction with NaBH4 - ethanol, to afford the previously obtained product (IV), which is reduced with H2 over Pd/C in ethanol.
The reaction of methyl 5-bromoacetylsalicylate (I) with benzyl tert-butylamine (II) in methyl ethyl ketone gives methyl 5-(N-benzyl-N-tert-butyl-gycyl)salicylate (III), which is reduced with LiAlH4 in refluxing THF yielding alpha'-(N-benzyl-N-tert-butylami-nomethyl)-4-hydroxy-m-xylene-alpha,alpha'-diol (IV). Finally, this compound is debenzylated by hydrogenation with H2 over Pd/C in ethanol-water.