Reaction equation
[Br:1][C:2]1(Br)[CH2:16][CH2:15][C:5]2[N:6]=[C:7]([NH:9][C:10]([NH:12][CH2:13][CH3:14])=[O:11])[S:8][C:4]=2[C:3]1=[O:17].C1CCN2C(=NCCC2)CC1>C1COCC1>[Br:1][C:2]1[CH:16]=[CH:15][C:5]2[N:6]=[C:7]([NH:9][C:10]([NH:12][CH2:13][CH3:14])=[O:11])[S:8][C:4]=2[C:3]=1[OH:17]Participants
Conditions
- Temperature
- 20 °C
Procedure
A suspension of 1-(6,6-dibromo-7-oxo-4,5,6,7-tetrahydro-2-benzothiazolyl)-3-ethyl-urea 5 (7.78 g, 19.6 mmol) in THF (50 mL) was treated with DBU (8.79 mL, 58.8 mmol, 3.0 eq) dropwise at about 20° C. A dark green suspension was obtained while heat was generated upon addition of DBU. It was stirred at about 20° C. for about 18 hours. The reaction mixture was concentrated and the residue was treated with saturated NH4Cl (aq) solution to neutral. A light brown colored precipitate was obtained. It was filtered off and washed with H2O (2×50 mL), small amount of MeOH and CH2Cl2, and finally dried under vacuum to give 4.83 g (78%) of the desired compound 6. 1H NMR (DMSO) δ 10.68 (br s, 1H, NH), 7.43 (d, 1H, J=8.5 Hz, ArH), 7.08 (d, 1H, J=8.5 Hz, ArH), 6.70 (br s, 1H, NH), 3.18 (m, 2H, CH2), 1.09 (t, 3H, J=7.2 Hz, CH3). LC/MS 316 (MH+); RP-HPLC RT 2.80 minutes.
Workup
- customA dark green suspension was obtained
- temperaturewhile heat
- concentrationThe reaction mixture was concentrated
- additionthe residue was treated with saturated NH4Cl (aq) solution to neutral
- customA light brown colored precipitate was obtained
- filtrationIt was filtered off
- washwashed with H2O (2×50 mL), small amount of MeOH and CH2Cl2
- customfinally dried under vacuum
Sources & evidence
- ORD record
- ord-4f2e74aefc354a3f8e93f452a584a7ad
- Source dataset
- uspto-grants-2006_08
- Patent number
- US07091227B2
Linked notes
Loading…