2-Chloro-N,N-dimethylethylamine → Deacetyldiltiazem
Reaction equation
[OH:1][C@H:2]1[C:8](=[O:9])[NH:7][C:6]2[CH:10]=[CH:11][CH:12]=[CH:13][C:5]=2[S:4][C@H:3]1[C:14]1[CH:19]=[CH:18][C:17]([O:20][CH3:21])=[CH:16][CH:15]=1.C(OCC)(=O)C.[CH3:28][N:29]([CH2:31][CH2:32]Cl)[CH3:30].C([O-])([O-])=O.[K+].[K+]>O>[CH3:28][N:29]([CH3:30])[CH2:31][CH2:32][N:7]1[C:6]2[CH:10]=[CH:11][CH:12]=[CH:13][C:5]=2[S:4][C@@H:3]([C:14]2[CH:19]=[CH:18][C:17]([O:20][CH3:21])=[CH:16][CH:15]=2)[C@@H:2]([OH:1])[C:8]1=[O:9]Participants
Procedure
A 5-L three-necked flask equipped with a heating mantle, a mechanical stirrer and a condenser was charged with 162 g (0.54 mol) of (+)-(2S,3S)-2,3-dihydro-3-hydroxy-2-(4-methoxyphenyl)-1,5-benzothiazepin-4(5H)-one and then 1 L of ethyl acetate. After stirring to dissolve the solution, 100 g (0.694 mol) of dimethylaminoethyl chloride.HC1 was added in one portion followed by 300 g (2.16 mol) of finely ground K2CO3 and 5 mL of H2O. (The 5 ml. of water was essential to cause a reaction between the phases, while addition of much more water would have resulted in gummy mixture that was difficult to filter.) This heterogeneous mixture was rapidly stirred at reflux for 5 hours. By thin layer chromatography (8:1, CH2C12 -MeOH, short wave UV), reaction was complete and therefore the mixture was allowed to cool to room temperature, filtered through a sintered glass funnel and washed with 100 mL 1:1 hexanes-ethyl acetate. The solvent was evaporated and on standing the oil crystallized. Recrystallization from ether gave 140 g (70%) of colorless crystalline (+)-(2S,3S)-5-[2-(dimethylamino)ethyl]-2,3-dihydro-3-hydroxy-2-(4-methoxyphenyl)-1,5-benzothiazepin-4(5H)-one, m.p. 79-81° C., [α]D20=+ 156.4°(C=1.0; CHC13).
Workup
- customA 5-L three-necked flask equipped with a heating mantle, a mechanical stirrer and a condenser
- additionHC1 was added in one portion
- customa reaction between the phases
- customwould have resulted in gummy mixture that
- filtrationto filter
- stirring) This heterogeneous mixture was rapidly stirred
- temperatureat reflux for 5 hours
- customBy thin layer chromatography (8:1, CH2C12 -MeOH, short wave UV), reaction
- filtrationfiltered through a sintered glass funnel
- washwashed with 100 mL 1:1 hexanes-ethyl acetate
- customThe solvent was evaporated
- customcrystallized
- customRecrystallization from ether
Sources & evidence
- ORD record
- ord-ceed1bc369f54150ad8bb952fcdc6f41
- Source dataset
- uspto-grants-1991_04
- Patent number
- US05008411
Reaction notes
Loading…