反应详情

To a solution of (R)-tert-butyl 2-(methoxy(methyl)carbamoyl)morpholine-4-carboxylate (1.37 g, 5.0 mmol) in THF (10 mL) at −20° C., there was added (4-methoxybutyl)magnesium chloride in THF (1.47 M, 10.2 mL, 15.0 mmol) dropwise such that the temperature remained below −20° C. After addition, the resulting solution was warmed to rt, and quenched with 1 N aq HCl (10 mL). The organic layer was separated, and the aqueous layer was extracted with ether (3×5 mL). The combined organic layers were washed with satd aq NaHCO3 (10 mL) and brine (5 mL), and dried over Na2SO4. The solvent was then removed in vacuo to give (R)-tert-butyl 2-(5-methoxypentanoyl)morpholine-4-carboxylate (1.41 g, 93%), which was used for the next step without purification; MS m/s 324 (M+Na+).

1. customremained below −20° C
2. additionAfter addition
3. customquenched with 1 N aq HCl (10 mL)
4. customThe organic layer was separated
5. extractionthe aqueous layer was extracted with ether (3×5 mL)
6. washThe combined organic layers were washed with satd aq NaHCO3 (10 mL) and brine (5 mL)
7. dry with materialdried over Na2SO4
8. customThe solvent was then removed in vacuo