Nifedipine → N-Methylnifedipine

HRID 399373Notes

Reaction equation

[CH3:1][C:2]1[NH:7][C:6]([CH3:8])=[C:5]([C:9]([O:11][CH3:12])=[O:10])[CH:4]([C:13]2[CH:14]=[CH:15][CH:16]=[CH:17][C:18]=2[N+:19]([O-:21])=[O:20])[C:3]=1[C:22]([O:24][CH3:25])=[O:23].[H-].[Na+].CI.[C:30](OCC)(=O)C>O1CCCC1.CC(CC(C)=O)C.CCCCCC>[CH3:1][C:2]1[N:7]([CH3:30])[C:6]([CH3:8])=[C:5]([C:9]([O:11][CH3:12])=[O:10])[CH:4]([C:13]2[C:18]([N+:19]([O-:21])=[O:20])=[CH:17][CH:16]=[CH:15][CH:14]=2)[C:3]=1[C:22]([O:24][CH3:25])=[O:23]

Participants

Conditions

Temperature: 38 °C

Procedure

12 g of nifedipine was disclosed in 50 ml of tetrahydrofuran in a nitrogen atmosphere. 1.66 g of a sodium hydride/oil dispersion (60% NaH) was added under agitation. Following agitation for some time, 10 ml of methyl iodide was added, and the resulting mixture was agitated for 1 hour at 38° C. 200 ml of ethyl acetate was then added. The resulting organic layer was washed several times with water, and was then dehydrated with sodium sulfate. The sodium sulfate was filtered out, and the solvent was removed. The solid obtained was dissolved in 200 ml of MIBK, and hexane was added producing 8.9 g of N-methylnifedipine in the form of yellow crystals. This compound had a melting point of 184° to 187° C.; an infrared absorption spectrum of 1690 cm-1 ; C=O, 1524 cm-1 ; N--O), and a proton-NMR spectrum (solvent: CDCl3) of 2.5 (6 H, methyl), 3.3 (3H, N-methyl), 3.6 (6H, O-methyl), 5.7 (1H, C--H, 7.2-7.6 (4H, C--H in aromatic nucleus).

Workup

additionwas added
washThe resulting organic layer was washed several times with water
filtrationThe sodium sulfate was filtered out
customthe solvent was removed
customThe solid obtained

Sources & evidence

ORD record: ord-df6e601094554948acb93bc45d40cf8c
Source dataset: uspto-grants-1998_10
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US05820944

Reaction notes

Loading…