The condensation of 3,4-dimethylbenzyl chloride (I) with diethyl malonate (II) by means of sodium ethoxide ethanol gives the diethyl 2-(3,4-dimethylbenzyl)malonate (III), which by treatment with aqueous refluxing NaOH and the with refluxing aqueous sulfuric acid yields 3-(3,4-dimethylphenyl)propionic acid (IV). The reaction of (IV) with refluxing SOCl2 affords the corresponding acyl chloride (V), which is treated with ammonia providing the amide (VI). The reduction of (VI) with LiAlH4 in refluxing THF gives 3-(3,4-dimethylphenyl)propylamine (VII), which by condensation with 2-(4-hydroxy-3-methoxyphenyl)acetic acid (VIII) by heating at 150 C yields the corresponding amide (IX). The alkylation of the phenolic group of (IX) with 1,2-dibromoethane (X) and NaH in refluxing THF affords the 2-bromoethoxy derivative (XI), which by treatment with NaN3 and Bu4NBr in refluxing benzene gives the 2-azidoethoxy derivative (XII). Finally, this compound is reduced with H2 over Pd/C in ethyl acetate to afford the target compound.

The 2-chloroethylation of ethyl homovanillate (I) with 1-bromo-2-chloroethane and K2CO3 in acetone gives ethyl 2-[4-(2-chloroethoxy)-3-methoxyphenyl]acetate (II), which is treated with sodium azide in toluene followed by hydrolysis with aqueous NaOH in MeOH, yielding 2-[4-(2-azidoethoxy)-3-methoxyphenyl]acetic acid (IV). The reaction of (IV) with SOCl2 and Et3N affords the acyl chloride (V). The reaction of 3-iodo-o-xylene (VI) and acrylonitrile under the Heck reaction conditions [Pd(OAc)2, tri-o-tolylphosphine and Et3N in MeCN] gives an isomeric mixture of 3-(3,4-dimethyl-phenyl)-2-propenenitrile (VII), which is hydrogenated with Pd/C followed by Raney-Ni to provide 3-(3,4-dimethylphenyl)propylamine (IX). The coupling reaction between the acyl chloride (V) and amine (IX) with Et3N in CH2Cl2 gives the amide (X). Finally, Pd/C catalyzed hydrogenation of this compound affords 2-[4-(2-aminoethoxy)-3-methoxyphenyl]-N-[3-(3,4-dimethylphenyl)propyl]acetamide.

The condensation of 3,4-dimethylbenzyl chloride (I) with diethyl malonate (II) by means of sodium ethoxide ethanol gives the diethyl 2-(3,4-dimethylbenzyl)malonate (III), which by treatment with aqueous refluxing NaOH and the with refluxing aqueous sulfuric acid yields 3-(3,4-dimethylphenyl)propionic acid (IV). The reaction of (IV) with refluxing SOCl2 affords the corresponding acyl chloride (V), which is treated with ammonia providing the amide (VI). The reduction of (VI) with LiAlH4 in refluxing THF gives 3-(3,4-dimethylphenyl)propylamine (VII), which by condensation with 2-(4-hydroxy-3-methoxyphenyl)acetic acid (VIII) by heating at 150 C yields the corresponding amide (IX). The alkylation of the phenolic group of (IX) with 1,2-dibromoethane (X) and NaH in refluxing THF affords the 2-bromoethoxy derivative (XI), which by treatment with NaN3 and Bu4NBr in refluxing benzene gives the 2-azidoethoxy derivative (XII). Finally, this compound is reduced with H2 over Pd/C in ethyl acetate to afford the target compound.

The condensation of 3,4-dimethylbenzyl chloride (I) with diethyl malonate (II) by means of sodium ethoxide ethanol gives the diethyl 2-(3,4-dimethylbenzyl)malonate (III), which by treatment with aqueous refluxing NaOH and the with refluxing aqueous sulfuric acid yields 3-(3,4-dimethylphenyl)propionic acid (IV). The reaction of (IV) with refluxing SOCl2 affords the corresponding acyl chloride (V), which is treated with ammonia providing the amide (VI). The reduction of (VI) with LiAlH4 in refluxing THF gives 3-(3,4-dimethylphenyl)propylamine (VII), which by condensation with 2-(4-hydroxy-3-methoxyphenyl)acetic acid (VIII) by heating at 150 C yields the corresponding amide (IX). The alkylation of the phenolic group of (IX) with 1,2-dibromoethane (X) and NaH in refluxing THF affords the 2-bromoethoxy derivative (XI), which by treatment with NaN3 and Bu4NBr in refluxing benzene gives the 2-azidoethoxy derivative (XII). Finally, this compound is reduced with H2 over Pd/C in ethyl acetate to afford the target compound.

The 2-chloroethylation of ethyl homovanillate (I) with 1-bromo-2-chloroethane and K2CO3 in acetone gives ethyl 2-[4-(2-chloroethoxy)-3-methoxyphenyl]acetate (II), which is treated with sodium azide in toluene followed by hydrolysis with aqueous NaOH in MeOH, yielding 2-[4-(2-azidoethoxy)-3-methoxyphenyl]acetic acid (IV). The reaction of (IV) with SOCl2 and Et3N affords the acyl chloride (V). The reaction of 3-iodo-o-xylene (VI) and acrylonitrile under the Heck reaction conditions [Pd(OAc)2, tri-o-tolylphosphine and Et3N in MeCN] gives an isomeric mixture of 3-(3,4-dimethyl-phenyl)-2-propenenitrile (VII), which is hydrogenated with Pd/C followed by Raney-Ni to provide 3-(3,4-dimethylphenyl)propylamine (IX). The coupling reaction between the acyl chloride (V) and amine (IX) with Et3N in CH2Cl2 gives the amide (X). Finally, Pd/C catalyzed hydrogenation of this compound affords 2-[4-(2-aminoethoxy)-3-methoxyphenyl]-N-[3-(3,4-dimethylphenyl)propyl]acetamide.

The 2-chloroethylation of ethyl homovanillate (I) with 1-bromo-2-chloroethane and K2CO3 in acetone gives ethyl 2-[4-(2-chloroethoxy)-3-methoxyphenyl]acetate (II), which is treated with sodium azide in toluene followed by hydrolysis with aqueous NaOH in MeOH, yielding 2-[4-(2-azidoethoxy)-3-methoxyphenyl]acetic acid (IV). The reaction of (IV) with SOCl2 and Et3N affords the acyl chloride (V). The reaction of 3-iodo-o-xylene (VI) and acrylonitrile under the Heck reaction conditions [Pd(OAc)2, tri-o-tolylphosphine and Et3N in MeCN] gives an isomeric mixture of 3-(3,4-dimethyl-phenyl)-2-propenenitrile (VII), which is hydrogenated with Pd/C followed by Raney-Ni to provide 3-(3,4-dimethylphenyl)propylamine (IX). The coupling reaction between the acyl chloride (V) and amine (IX) with Et3N in CH2Cl2 gives the amide (X). Finally, Pd/C catalyzed hydrogenation of this compound affords 2-[4-(2-aminoethoxy)-3-methoxyphenyl]-N-[3-(3,4-dimethylphenyl)propyl]acetamide.