Reaktion #446774
ord-822501afb6d44eaf9bac5979fc153d8d
Reaktionsgleichung
Reagenzien
Reaktionsbedingungen
Vorschrift
A dl-compound among the compound (I) is treated in a conventional manner with a resolution agent such as brucine, cinchonine, quinine and quaternary salts thereof or the like optical active alkaloid, α-phenethylamine (d- and l-compounds), 3-aminomethylpinane (d- and l-compounds) or the like to obtain respective diastereomer salts and then the salts are separated in a conventional manner to obtain the optical active compounds (I). The method will be explained in more detail, as to the case of that cinchonine-methohydoxide or quinine-methohydroxide is employed as the optical resolution agent. dl-compound among the compounds (I) is dissolved in methanol, ethanol, acetone or the like organic solvent, quinine-methohydroxide solution in equivalent amount is added thereto, and then the mixture is concentrated in vacuo to obtain N-methylquinium salt of the corresponding compound, as an amorphous substance. The amorphous substance is dissolved in methanol ethanol, isopropanol, acetone or the like organic solvent and the solution is left to stand to form crystals. The crystals are obtained through a filtration of the solution and subjected to recrystallization to obtain N-methylquinium salt of the d-compound. The salt was treated with hydrochloric acid and recrystallized from an organic solvent in a conventional manner to obtain the desired d-compound (I). While the mother liquor, from which the d-compound was filtered off, is concentrated to obtain N-methylquinium salts of the compounds mainly containing the l-compound and thus the salts are treated with hydrochloric acid to obtain crystals of the compounds containing mainly the l-compound. The crystals are dissolved in methanol, ethanol, acetone or the like organic solvent, cinchonine-methohydrooxide solution in equivalent amount is added thereto, and the mixture is concentrated in vacuo to obtain N-methylcinchonium salts of the compounds containing mainly the l-compound. The salts are dissolved in methanol, ethanol, isopropanol, acetone or the like organic solvent and left to stand to obtain crystals which are recrystallized to obtain N-methylcinchonium salt of the l-compound. The salt is treated with hydrocholoric acid and recrystallized from an organic solvent to obtain the desired l-compound (I).