The condensation of 3-methoxybenzaldehyde (I) with acetone (II) by means of NaOH gives 1-(3-methoxyphenyl)-1-buten-3-one (III), which is hydrogenated with H2 over Pd/C in methanol yielding 1-(3-methoxyphenyl)-3-butanone (IV). The iodination of (IV) with I2-silver acetate in acetic acid affords 1-(2-iodo-5-methoxyphenyl)-3-butanone (V), which is reductocondensed with methylamine and sodium cyanoborohydride in methanol giving 2-iodo-5-methoxy-N,alpha-dimethylphenylpropanamine (VI). The acylation of (VI) with 3,4-dimethoxyphenylacetyl chloride (VII) by means of triethylamine in dichloromethane yields the corresponding acetamide (VIII), which is reduced with borane-THF complex affording the corresponding tertiary amine (IX), which is finally condensed with phenylacetylene (X) by means of butyllithium in THF.

The condensation of 3-methoxybenzaldehyde (I) with acetone (II) by means of NaOH gives 1-(3-methoxyphenyl)-1-buten-3-one (III), which is hydrogenated with H2 over Pd/C in methanol yielding 1-(3-methoxyphenyl)-3-butanone (IV). The iodination of (IV) with I2-silver acetate in acetic acid affords 1-(2-iodo-5-methoxyphenyl)-3-butanone (V), which is reductocondensed with methylamine and sodium cyanoborohydride in methanol giving 2-iodo-5-methoxy-N,alpha-dimethylphenylpropanamine (VI). The acylation of (VI) with 3,4-dimethoxyphenylacetyl chloride (VII) by means of triethylamine in dichloromethane yields the corresponding acetamide (VIII), which is reduced with borane-THF complex affording the corresponding tertiary amine (IX), which is finally condensed with phenylacetylene (X) by means of butyllithium in THF.

The condensation of 3-methoxybenzaldehyde (I) with acetone (II) by means of NaOH gives 1-(3-methoxyphenyl)-1-buten-3-one (III), which is hydrogenated with H2 over Pd/C in methanol yielding 1-(3-methoxyphenyl)-3-butanone (IV). The iodination of (IV) with I2-silver acetate in acetic acid affords 1-(2-iodo-5-methoxyphenyl)-3-butanone (V), which is reductocondensed with methylamine and sodium cyanoborohydride in methanol giving 2-iodo-5-methoxy-N,alpha-dimethylphenylpropanamine (VI). The acylation of (VI) with 3,4-dimethoxyphenylacetyl chloride (VII) by means of triethylamine in dichloromethane yields the corresponding acetamide (VIII), which is reduced with borane-THF complex affording the corresponding tertiary amine (IX), which is finally condensed with phenylacetylene (X) by means of butyllithium in THF.