Sulfuric Acid → (2S,3R)-1-(dimethylamino)-3-(3-methoxyphenyl)-2-methyl-pentan-3-yl 4-methylbenzenesulfonate

Participants

Reaction Conditions

Reaction Steps

Accordingly the compound (2S,3R)-1-(dimethylamino)-3-(3-methoxyphenyl)-2-methyl pentan-3-ol of Formula-V was charged in the solvent tetrahydrofuran and under stirring charged concentrated sulfuric acid at temperature of 20-30° C. The reaction mixture is stirred and charged methanesulfonic acid or para toluenesulfonic acid and solvent cyclohexane. Stirred and raised the temperature to reflux. Maintained the reaction mass at reflux temperature for 3-5 hours with simultaneous removal of water. Cooled the reaction mass to 20° C. and quenched with water. The pH of the quenched reaction solution was adjusted to 8-9 using dilute sodium hydroxide solution. The reaction solution was extracted with cyclohexane. Separated the organic layer and concentrated under reduced pressure to get the compound (2S,3R)-1-(dimethylamino)-3-(3-methoxyphenyl)-2-methyl pentan-3-yl methane sulfonate of Formula IXA or (2S,3R)-1-(dimethylamino)-3-(3-methoxyphenyl)-2-methyl-pentan-3-yl 4-methylbenzenesulfonate of Formula IXB.

Provenance & Evidence