METHOD FOR PREPARING(-)-CIS-3-HYDROXY-1-METHYL-4-(2,4,6-TRIMETHOXYPHENYL)PIPERIDINE AND INTERMEDIATES COMPOUNDS Russian patent published in 2005 - IPC

FIELD: organic chemistry, chemical technology.

SUBSTANCE: invention elates to the improved method for preparing (-)-cis-3-hydroxy-1-methyl-4-(2,4,6-trimethoxyphenyl)piperidine. Method involves conversion of 1-methylpiperidine-4-one to hydrobromide followed by interaction with bromide to obtain 3-(R,S)-bromo-1-methyl-4-oxopiperidine hydrobromide and then with 1,3,5-trimethoxybenzene to obtain 3-(R,S)-bromo-1-methyl-4-(2,4,6-trimethoxyphenyl)-1,2,3,6-tetrahydropridine hydrobromide. Then by addition of the reaction solution with organic solvent 3-(R,S)-bromo-1-methyl-4-(2,4,6-trimethoxyphenyl)-1,2,3,6-tetrahydropyridine hydrobromide is isolated firstly as a solid substance and then product is mixed with water and converted by stirring to 3-(R,S)-bromo-1-methyl-4-(2,4,6-trimethoxyphenyl)-1,2,3,6-tetrahydropyridine. Prepared product is hydrogenated catalytically for preparing racemic 3,4-cis-alcohol and by cleavage of racemate by using chiral accessory reagents (-)-cis-3-hydroxy-1-methyl-4-(2,4,6-trimethoxyphenyl)piperidine is prepared from racemic 3,4-cis-alcohol as a pure enantiomer. Proposed method provides simplifying a process for preparing abovementioned product and to reduce duration of process due to exclusion the hydroborating stage, oxidation by Swern, reduction with sodium boron hydride used in preparing the same product by the known method. Also, invention describes intermediates compounds: 3-(R,S)-bromo-1-methyl-4-(2,4,6-trimethoxyphenyl)-1,2,3,6-tetrahydropyridine hydrobromide and 3-(R,S)-hydroxy-1-methyl-4-(2,4,6-trimethoxyphenyl)-1,2,3,6-tetrahydropyridine.

EFFECT: improved preparing method.

3 cl, 10 ex