反応 #1546902

反応方程式

Water

N-tert-Butyloxycarbonyl-4-piperidone

2-phenylpiperidine

sodium cyanoborohydride

→

1-tert-Butyloxycarbonyl-4-[2-phenylpiperidin-1-yl]piperidine

収率 3.0%

溶媒

ethyl acetate

methanol

反応条件

後処理

1. 1
   その他to give a granular precipitate which
2. 2
   その他was removed by filtration through celite
3. 3
   その他The filtrate was partitioned between water-ethyl acetate
4. 4
   その他the organic phase separated
5. 5
   乾燥dried (MgSO4)
6. 6
   濃縮concentrated
7. 7
   workup.DISSOLUTIONThe residue was dissolved in ethyl acetate
8. 8
   洗浄washed with a saturated aqueous solution of citric acid
9. 9
   抽出extracted into ethyl acetate
10. 10
    乾燥The organic phase was dried (MgSO4)
11. 11
    濃縮concentrated
12. 12
    その他The residue was chromatographed
13. 13
    その他to afford a partially purified mixture, which
14. 14
    洗浄The organic phase was washed with a saturated aqueous solution of citric acid
15. 15
    その他The aqueous phase was separated
16. 16
    抽出extracted with ethyl acetate
17. 17
    乾燥The organic phase was dried (MgSO4)
18. 18
    濃縮concentrated
19. 19
    その他to give the product in 3% yield

実験手順

N-tert-Butyloxycarbonyl-4-piperidone (5 g), 2-phenylpiperidine (4.03 g) and titanium isopropoxide (8.9 ml) were stirred at room temperature under a nitrogen atmosphere for 3 h. The resulting orange solution was diluted with methanol (40 ml), treated with sodium cyanoborohydride (1.6 g), and stirred for 20 h. Water (50 ml) was added to give a granular precipitate which was removed by filtration through celite. The filtrate was partitioned between water-ethyl acetate, the organic phase separated, dried (MgSO4) and concentrated. The residue was dissolved in ethyl acetate and washed with a saturated aqueous solution of citric acid. The aqueous phase was basified to pH10 using 4N sodium hydroxide, and extracted into ethyl acetate. The organic phase was dried (MgSO4) and concentrated. The residue was chromatographed using ethyl acetate-petroleum ether (20:80 to 50:50) to afford a partially purified mixture, which was dissolved in ethyl acetate. The organic phase was washed with a saturated aqueous solution of citric acid. The aqueous phase was separated, basified to pH10 using 4N sodium hydroxide and extracted with ethyl acetate. The organic phase was dried (MgSO4) and concentrated to give the product in 3% yield. δH (250 MHz, CDCl3) 1.16-1.79 (19H, m), 2.21-2.29 (2H, m), 2.41-2.50 (2H, m), 2.90-3.04 (1H, m), 3.36-3.44 (1H, m), 3.92-4.10 (2H, m), 7.16-7.40 (5H, m).

出典