This compound has been obtained by three related ways: 1.- The Grignard condensation of ethyl cyclohexanecarboxylate (I) with benzylmagnesium bromide (II) in THF gives 1-cyclohexyl-2-phenylethanone (III), which is condensed with bromoacetaldehyde diethyl acetal (IV) by means of potassium tert-butoxide in DMSO to yield 4-cyclohexyl-4-oxo-3-phenylbutyraldehyde diethylacetal (V). The methylation of (V) by means of methyl iodide and potassium tert-butoxide in the same solvent affords 4-cyclohexyl-3-methyl-4-oxo-3-phenylbutyraldehyde diethylacetal (VI), which is treated with HCl in acetone to give the corresponding aldehyde (VII). The reductocondensation of (VII) with 1-(2-methoxyphenyl)piperazine (VIII) by means of sodium triacetoxyborohydride in dichloromethane/acetic acid yields 1-cyclohexyl-4-[4-(2-methoxyphenyl)piperazin-1-yl]-2-methyl-2-phenyl-1-butanone (X) as a racemic mixture, which is resolved by chiral chromatography over a Chiralpak AD column. 2.- The Grignard condensation of 2-phenylpropionaldehyde (XI) with cyclohexylmagnesium chloride (XII) in ethyl ether/THF gives 1-cyclohexyl-2-phenyl-1-propanol (XIII), which is oxidized with DMSO and P2O5 in dichloromethane yielding the corresponding ketone (XIV). The condensation of (XIV) with allyl bromide by means of potassium tert-butoxide in THF affords 1-cyclohexyl-2-methyl-2-phenyl-4-penten-1-one (XV), which is ozonolyzed with O3 in methanol catalyzed by a small amount of Sudan III affording the previously reported aldehyde (VII). 3.- The condensation of aldehyde (VII) with 1-(2-methoxyphenyl)piperazine (VIII) can also be performed in isopropyl acetate giving 1-cyclohexyl-4-[4-(2-methoxyphenyl)piperazin-1-yl]-2-methyl-2-phenyl-3-buten-1-one (IX), which is hydrogenated with H2 over Pd/C in isopropanol to afford the previously reported racemic mixture (X).

This compound has been obtained by three related ways: 1.- The Grignard condensation of ethyl cyclohexanecarboxylate (I) with benzylmagnesium bromide (II) in THF gives 1-cyclohexyl-2-phenylethanone (III), which is condensed with bromoacetaldehyde diethyl acetal (IV) by means of potassium tert-butoxide in DMSO to yield 4-cyclohexyl-4-oxo-3-phenylbutyraldehyde diethylacetal (V). The methylation of (V) by means of methyl iodide and potassium tert-butoxide in the same solvent affords 4-cyclohexyl-3-methyl-4-oxo-3-phenylbutyraldehyde diethylacetal (VI), which is treated with HCl in acetone to give the corresponding aldehyde (VII). The reductocondensation of (VII) with 1-(2-methoxyphenyl)piperazine (VIII) by means of sodium triacetoxyborohydride in dichloromethane/acetic acid yields 1-cyclohexyl-4-[4-(2-methoxyphenyl)piperazin-1-yl]-2-methyl-2-phenyl-1-butanone (X) as a racemic mixture, which is resolved by chiral chromatography over a Chiralpak AD column. 2.- The Grignard condensation of 2-phenylpropionaldehyde (XI) with cyclohexylmagnesium chloride (XII) in ethyl ether/THF gives 1-cyclohexyl-2-phenyl-1-propanol (XIII), which is oxidized with DMSO and P2O5 in dichloromethane yielding the corresponding ketone (XIV). The condensation of (XIV) with allyl bromide by means of potassium tert-butoxide in THF affords 1-cyclohexyl-2-methyl-2-phenyl-4-penten-1-one (XV), which is ozonolyzed with O3 in methanol catalyzed by a small amount of Sudan III affording the previously reported aldehyde (VII). 3.- The condensation of aldehyde (VII) with 1-(2-methoxyphenyl)piperazine (VIII) can also be performed in isopropyl acetate giving 1-cyclohexyl-4-[4-(2-methoxyphenyl)piperazin-1-yl]-2-methyl-2-phenyl-3-buten-1-one (IX), which is hydrogenated with H2 over Pd/C in isopropanol to afford the previously reported racemic mixture (X).

The alkylation of phenylacetylene (I) with AlMe3 and ZnCl2CP2 gives the alpha-methylstyrene (II), which is treated with paraformaldehyde and BuLi to yield 3-phenyl-2-buten-1-ol (III). The reaction of (III) with NCS and DMS affords the butenyl chloride (IV), which is treated with trichlorosilane, TEA and CuCl to provide the allylic trichlorosilane (V). The condensation of (V) with benzaldehyde (VI) by means of the chiral catalyst (VII) and tetrabutylammonium iodide in dichloromethane gives the chiral diphenylcarbinol (VIII), which is submitted to hydroboration by means of 9-BBN and NaBO3 to yield the diol (IX). The selective, two step reduction of one phenyl group of (IX) with H2 over Rh/alumina and H2 over Pt/C affords the chiral cyclohexyl-butanediol derivative (X), which is oxidized by means of (COCl)2, DMSO and TEA in dichloromethane to provide the keto-aldehyde (XI). Finally, this compound is reductocondensed with 1-(2-methoxyphenyl)piperazine (XII) by means of NaBH(OAc)3 in 1,2-dichloroethane to give the target disubstituted piperazine.