[CH:1]([O:4][C:5](=[O:14])[C:6]1[CH:11]=[CH:10][C:9]([Br:12])=[CH:8][C:7]=1[CH3:13])([CH3:3])[CH3:2].[Br:15]N1C(=O)CCC1=O.N(C(C)(C)C#N)=NC(C)(C)C#N>C(Cl)(Cl)(Cl)Cl>[CH:1]([O:4][C:5](=[O:14])[C:6]1[CH:11]=[CH:10][C:9]([Br:12])=[CH:8][C:7]=1[CH2:13][Br:15])([CH3:3])[CH3:2]A solution of 4-bromo-2-methyl-benzoic acid isopropyl ester (Intermediate 117, 6.12 g, 23.8 mmol) in carbon tetrachloride (120 mL) was treated with N-bromosuccinimide (4.6 g, 26.18 mmol) and 2,2′-azobisisobutyronitrile (0.6 g) and the resulting reaction mixture was refluxed overnight. It was cooled to ambient temperature, the solids were filtered off and washed with 1:1 hexane:diethyl ether, and the filtrate and washings were evaporated in vacuo to afford an oil (5.1 g, 64%) that was used as such for the next step.
Wird geladen…
