2-Bromo-4'-nitroacetophenone → alpha-(4-Picolylthio)p-nitroacetophenone

Reaction equation

C[O-].[Na+].[N:4]1[CH:9]=[CH:8][C:7]([CH2:10][SH:11])=[CH:6][CH:5]=1.Br[CH2:13][C:14]([C:16]1[CH:21]=[CH:20][C:19]([N+:22]([O-:24])=[O:23])=[CH:18][CH:17]=1)=[O:15]>C(O)C>[N:4]1[CH:9]=[CH:8][C:7]([CH2:10][S:11][CH2:13][C:14]([C:16]2[CH:17]=[CH:18][C:19]([N+:22]([O-:24])=[O:23])=[CH:20][CH:21]=2)=[O:15])=[CH:6][CH:5]=1

Participants

Procedure

Under a nitrogen atmosphere, sodium methoxide (0.52 g., 9.6 mmoles) was dissolved in 15 ml. of absolute ethanol and cooled to 0°-5° C. 4-Picolyl mercaptan (1.2 g., 9.6 mmoles) in 15 ml. of ethanol was added over 5 minutes time. Alpha-bromo-p-nitro-acetophenone (2.3 g., 9.6 mmoles) in 20 ml. of warm ethanol was then added over 5 minutes, the mixture was warmed to room temperature and left to stir for approximately 16 hours. The reaction mixture was filtered and the filtrate concentrated to an oil (4.3 g.). The oil was chromatographed on 175 g. of silica gel with 1:1 hexane:ethyl acetate as eluant. Product-containing fractions were combined and evaporated to yield alpha-(4-picolylthio)-p-nitro-acetophenone [1.40 g.; oil; pnmr/CDCl3 /TMS/delta: 6.5 (3, 4H), 2.7 (d, 2H), 1.9 (d, 4H), 1.5 (d, 2H); mass spectra: m/e calcd.: 288; found: 288, 242, 165, 150, 138, 124, 104, 92, 76, 65, 39; ir (film): 3-3.5, 5.95, 6.25, 6.55, 7.35, 7.85, 11.70,μ].