反应详情

温度

90 °C

A mixture of methyl (2R,3R,4S,5S)-3-benzyloxy-4-methoxy-5-methyltetrahydro-2H-pyran-2-carboxylate (7 mg, 0.024 mmole) and heptylamine (0.1 ml, 0.68 mmole) was heated at 90° C. for 3 hr. The reaction mixture was adjusted to pH 3 with 0.1N aqueous HCl, and partitioned between ether (10 ml) and water (10 ml). The ether layer was dried over anhydrous magnesium sulfate and evaporated to dryness under reduced pressure. A solution of the resulting crude amide in MeOH (5 ml) was stirred under hydrogen atmosphere in the presence of Pd-black (5 mg) at room temperature for 12 hr. The catalyst was removed by filtration and washed with methanol (2 ml×2). The combined filtrate and washings were evaporated to dryness under reduced pressure. The residue was chromatographed on silica gel using AcOEt/n-hexane (4:6) as an eluent to give (2R,3R,4S,5S)-N-heptyl-3-hydroxy-4-methoxy-5-methyltetrahydro-2H-pyran- 2-carboxamide (3.4 mg, 50% yield) as an oil; FAB-MS: m/z 288 (MH+). 1H-NMR (CDCl3)d: 0.91 (3H,t,J=6.5 Hz), 1.05 (3H,d,J=7 Hz), 1.25 (10H,br.s), 2.2 (1H,m), 3.10~3.6 (7H,br.m), 3.3 (3H,s), 3.81 (1H,dd,J=2.5 & 12 Hz), 8.0 (1H,br.s).

1. custompartitioned between ether (10 ml) and water (10 ml)
2. dry with materialThe ether layer was dried over anhydrous magnesium sulfate
3. customevaporated to dryness under reduced pressure
4. customThe catalyst was removed by filtration
5. washwashed with methanol (2 ml×2)
6. customThe combined filtrate and washings were evaporated to dryness under reduced pressure
7. customThe residue was chromatographed on silica gel