p-Tolyl methyl sulfone → 4-(Methylsulfonyl)benzyl Bromide
反応式
[C:1]1([CH3:11])[CH:6]=[CH:5][C:4]([S:7]([CH3:10])(=[O:9])=[O:8])=[CH:3][CH:2]=1.[Br:12]N1C(=O)CCC1=O>C(Cl)(Cl)(Cl)Cl>[CH3:10][S:7]([C:4]1[CH:5]=[CH:6][C:1]([CH2:11][Br:12])=[CH:2][CH:3]=1)(=[O:9])=[O:8]参加物
4
実験手順
Methyl p-tolyl sulfone (24 g, 0.14 mol) in 550 ml CCl4 was heated to reflux temperature, N-bromosuccinimide (17.8 g, 0.14 mol) was added in portions and the mixture was refluxed for 3 h. After cooling to room temperature, the mixture was filtered and the filtrate was concentrated to yield 4-methanesulfonylbenzyl bromide as a crystalline solid (32.9 g), 1H-NMR (CDCl3) δ 8.05 (d, 2H), 7.70 (d, 2H), 4.45 (s, 2H), 3.09 (s, 3H). To the crude product in water (200 ml) were added sodium sulfite (33.2 g, 264 mmol) and tetrabutylammonium bromide (0.41 g, 1.64 mmol), and the mixture was refluxed for 2 h. After cooling to room temperature the solution was extracted with ethyl acetate, the aqueous phase was then concentrated to half the volume and cooled. The precipitate was filtered off and dried under vacuum at 70° C. to yield sodium 4-methanesulfonyl-benzylsulfonate (33.3 g, quant.).