反应详情

温度

0 °C

1.71 g (10.7 mmol) of bromine were added in one portion to a solution of 1.35 g (10.7 mmol) of 4,4-dimethyl-cyclohexanone in methanol (10 ml) at −10° C. The reaction mixture was then stirred for 10 min at −10° C., for 30 min at 0° C. and finally for 8 h at RT. The reaction was then quenched by addition of water (5 ml) and stirred overnight at RT. Additional water was added (20 ml) leading to the formation of a precipitate that was collected by filtration. The crude 2-bromo-4,4-dimethyl-cyclohexanone (1.72 g, 78%) that was obtained as an orange solid was used in the next reaction step without further purification. 1HNMR (CDCl3, 300 MHz): δ 1.09 (s, 3H), 1.23 (s, 3H), 1.75 (m, 2H), 2.09 (t, J=13.1 Hz, 1H), 2.34 (ddd, J=13.3 and 6.1 and 2.8 Hz, 1H), 2.59 (m, 2H), 4.77 (dd, J=12.9 and 5.9 Hz, 1H).

1. customThe reaction was then quenched by addition of water (5 ml)
2. stirringstirred overnight at RT
3. additionAdditional water was added (20 ml)
4. filtrationwas collected by filtration