反应详情

温度

3 °C

A solution was prepared from 77 ml of methanol and 13.0 g of methyl 4-(oxoethylidene)cyclohexanecarboxylate and cooled to 3° C. with an ice-water bath. With vigorous stirring, 3.1 g of sodium borohydride was added in portions over 30 minutes. The reaction was allowed to stir for an additional hour at 3° C. before glacial acetic acid (1 ml) was added to quench the reaction and the methanol was removed under reduced pressure. The residue was taken up in 200 ml of dichloromethane and partitioned with 400 ml of water. The organic layer was separated and washed with 200 ml of saturated sodium chloride, dried over anhydrous sodium sulfate, filtered and concentrated under vacuum. The resulting oil was purified on the Prep LC (30% ethyl acetate/hexane, 250 ml/min., 2 min./cm, 2 columns, Rt =13 min.) to give 11.5 g of fairly pure product. Bulb-to-bulb distillation on the Kugelrohr at 150°-160° C./0.8 mm yielded 9.03 g (69%) of methyl 4-(2-hydroxyethylidene)cyclohexanecarboxylate. 1H NMR (CDCl3 60 MHz) δ 5.40 (t, 1 H); 4.10 (d, 2 H); 3.70 (s, 3 H); 2.9-1.3 (10 H).

1. additionwas added
2. customto quench
3. customthe reaction
4. customthe methanol was removed under reduced pressure
5. custompartitioned with 400 ml of water
6. customThe organic layer was separated
7. washwashed with 200 ml of saturated sodium chloride
8. dry with materialdried over anhydrous sodium sulfate
9. filtrationfiltered
10. concentrationconcentrated under vacuum
11. customThe resulting oil was purified on the Prep LC (30% ethyl acetate/hexane, 250 ml/min., 2 min./cm, 2 columns, Rt =13 min.)
12. customto give 11.5 g of fairly pure product
13. distillationdistillation on the Kugelrohr at 150°-160° C./0.8 mm