合成路线1

This compound can be prepared by several different ways: 1) The reaction ot 4-(chloromethyl)pyridine (I) with NaCN in toluene - water gives 4-(cyanomethyl)pyridine (II), which is condensed with methyl acrylate (III) yielding dimethyl 4-cyano 4-(4-pyridyl)pimelate (IV). The hydrolysis and decarboxylation of (IV) atfords 4-(4-pyridyl)pimelic acid (V), which is cyclized by means of potassium tert-butoxide giving 4-(4-pyridyl)cyclohexanone (VI). The acetylation of (VI) with acetic anhydride or acetylimidazole affords 2-acetyl(4-4 pyridyl)cyclohexanone (VII), which is finally cyclized with acetylacetamide (VIII) by means of dimethylamine. 2) The cyclization of (VII) with cyanoacetamide (IX) by means of piperidine gives 4-cyano-1-methyl-7-(4-pyridyl)-5,6,7,8-tetrahydro-3(2H)-isoquinolinone (X), which is finally treated with methyl magnesium iodide in ether. 3) The condensation of 4 bromopyridine (XI) and cyclohexanedione monoethyleneketal (XII) by means of butyllithium in THF gives 4-hydroxy-4-(4-pyridyil)cyclohexanone ethyleneketal (XIII), which is dehydrated by treatment with SOCl2 and then with NaOH to afford 4-(4-pyridyl)-3-cyclohexenone ethyleneketal (XIV). Finally, this compound is hydrolyzed with HCl and reduced with H2 over Pd/C in 0.5 N HCl yielding cyclohexanone (VII), already obtained.