反应详情

N-Methyl-N-nitrosourea (6.4 g, 31 mmol) was added to an ice-cooled mixture of 10% aqueous NaOH (250 g, 625 mmol) and Et2O (300 mL), and the mixture was stirred vigorously with ice cooling for 10 minutes. The ether layer was decanted into a dry, 1 L Erlenmeyer flask, and stirred with ice cooling as a solution of the product from Example 114A (3.00 g, 15.8 mmol) in ether (60 mL) was added. The yellow solution was stirred with ice cooling as Pd(OAc)2 (30 mg, 0.134 mmol) was added. After 1 hour, acetic acid (0.5 mL) was added to consume any excess diazomethane, and the reaction mixture was concentrated under vacuum to a gray oil. The residue was dissolved in EtOAc (50 mL) and washed with saturated NaHCO3(aq) (25 mL). The organic phase was concentrated under vacuum and the residue was purified by flash chromatography (silica gel, eluted with hexanes-EtOAc 100:0-90:10) to provide the title compound. 1H NMR (300 MHz, CD3OD) δ ppm −0.02-0.06 (m, 2H) 0.40 (ddd, J=8.1, 5.8, 4.1 Hz, 2H) 0.62-0.78 (m, 1H) 1.51 (q, J=7.1 Hz, 2H) 2.45 (t, J=7.3 Hz, 2H) 5.11 (s, 2H) 7.24-7.40 (m, 5H).

1. temperaturecooled
2. customThe ether layer was decanted into a dry, 1 L Erlenmeyer flask
3. additionwas added
4. additionwas added
5. waitAfter 1 hour
6. customto consume any excess diazomethane
7. concentrationthe reaction mixture was concentrated under vacuum to a gray oil
8. dissolutionThe residue was dissolved in EtOAc (50 mL)
9. washwashed with saturated NaHCO3(aq) (25 mL)
10. concentrationThe organic phase was concentrated under vacuum
11. customthe residue was purified by flash chromatography (silica gel, eluted with hexanes-EtOAc 100:0-90:10)