Cesium carbonate → Ethyl rac-2-[3-(4-chlorophenyl)-4-cyclopropyl-5-oxo-4,5-dihydro-1h-1,2,4-triazol-1-yl]propionate

HRID 660857Notes

Reaction equation

Br[CH:2]([CH3:8])[C:3]([O:5][CH2:6][CH3:7])=[O:4].C(=O)([O-])[O-].[Cs+].[Cs+].[Cl:15][C:16]1[CH:21]=[CH:20][C:19]([C:22]2[N:23]([CH:28]3[CH2:30][CH2:29]3)[C:24](=[O:27])[NH:25][N:26]=2)=[CH:18][CH:17]=1>C(#N)C>[Cl:15][C:16]1[CH:17]=[CH:18][C:19]([C:22]2[N:23]([CH:28]3[CH2:29][CH2:30]3)[C:24](=[O:27])[N:25]([CH:2]([CH3:8])[C:3]([O:5][CH2:6][CH3:7])=[O:4])[N:26]=2)=[CH:20][CH:21]=1

Participants

Conditions

Temperature: 85 °C

Procedure

384 mg (2.12 mmol) of ethyl 2-bromopropionate and 1.38 g (4.24 mmol) of caesium carbonate are added to 500 mg (2.12 mmol) of 5-(4-chlorophenyl)-4-cyclopropyl-2,4-dihydro-3H-1,2,4-triazol-3-one from Example 36A in 5 ml acetonitrile and the reaction mixture is heated at 85° C. overnight. It is then concentrated in vacuo, the residue is partitioned between water and dichloromethane, and the separated organic phase is dried over sodium sulphate and again evaporated. After purification of the residue by flash chromatography over silica gel (eluent: first dichloromethane, then dichloromethane/methanol 200:1), 729 mg (97% of theory) of the target compound are obtained.

Workup

concentrationIt is then concentrated in vacuo
customthe residue is partitioned between water and dichloromethane
dry with materialthe separated organic phase is dried over sodium sulphate
customagain evaporated
customAfter purification of the residue by flash chromatography over silica gel (eluent
customfirst dichloromethane, then dichloromethane/methanol 200:1), 729 mg (97% of theory) of the target compound are obtained

Sources & evidence

ORD record: ord-33b5651bcaa24a30bbe7abb571a57d20
Source dataset: uspto-grants-2011_12
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US08084481B2

Reaction notes

Loading…