1,2,3,6-Tetrahydro-1-methyl-4-(2,4,6-trimethoxyphenyl)-3-pyridinol → (3S,4R)-1-Methyl-4-(2,4,6-trimethoxyphenyl)-3-piperidinol
Reaction equation
[OH:1][CH:2]1[C:7]([C:8]2[C:13]([O:14][CH3:15])=[CH:12][C:11]([O:16][CH3:17])=[CH:10][C:9]=2[O:18][CH3:19])=[CH:6][CH2:5][N:4]([CH3:20])[CH2:3]1>O>[OH:1][C@H:2]1[C@@H:7]([C:8]2[C:9]([O:18][CH3:19])=[CH:10][C:11]([O:16][CH3:17])=[CH:12][C:13]=2[O:14][CH3:15])[CH2:6][CH2:5][N:4]([CH3:20])[CH2:3]1Participants
Reactant 1
Product 1
Reagents, catalysts & solvents 1
Procedure
Disclosed is a method for producing (−)cis-3-hydroxy-1-methyl-4-(2,4,6-trimethoxyphenyl)-piperidine characterized in that 1-methyl-piperidine-4-one is converted into hydrobromide, subsequently transformed with bromine into 3(R,S)-bromine-1-methyl-4-oxo-piperidine-hydrobromide and reacted with 1,3,5-trimethoxybenzol to form 3(R,S)-bromine-1-methyl-4-(2,4,6-trimethoxyphenyl)-1,2,3,6-tetrahydro-pyridine-hydrobromide. By stirring the reaction solution into an organic solvent, 3(R,S)-bromine-1-methyl-4-(2,4,6-trimethoxyphenyl)-1,2,3,6-tetrahydro-pyridine-hydrobromide is initially isolated as a solid and subsequently the product is mixed with water and converted into 3(R,S)-hydroxy-1-methyl-4-(2,4,6-trimethoxyphenyl)-1,2,3,6-tetrahydro-pyridine by means of stirring. The product thus prepared is catalytically hydrogenated into a racemic 3,4-cis-alcohol and subsequently, enantiomerically pure (−)cis-3-hydroxy-1-methyl-4-(2,4,6-trimethoxyphenyl)-piperidine is obtained by separation of racemic mixtures with chiral auxiliary reagents from racemic 3,4-cis alcohol.
Workup
- customis initially isolated as a solid
- customThe product thus prepared
Sources & evidence
- ORD record
- ord-d07d2ec2d0de4da785ec39fba72309ac
- Source dataset
- uspto-grants-2002_08
- Patent number
- US06437136B1
Reaction notes
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