反応 #89630

反応方程式

N-boc-glycine, allyl ester

allyl acrylate

lithium bis(trimethylsilylamide) tetrahydrofuran

→

3-allyl 1-tert-butyl 4-oxopyrrolidine-1,3-dicarboxylate

収率 63.0%

溶媒

tetrahydrofuran

tetrahydrofuran

反応条件

後処理

1. 1
   その他temperature below 10° C.
2. 2
   温度cooled (−40° C.)
3. 3
   その他to reach room temperature
4. 4
   workup.STIRRINGstirred 1 h
5. 5
   温度refluxed for 2 h
6. 6
   温度The mixture was cooled to room temperature
7. 7
   その他quenched with glacial acetic acid (2.5 mL)
8. 8
   濃縮concentrated
9. 9
   workup.DISSOLUTIONThe residual oil was dissolved in methylene chloride (300 mL)
10. 10
    洗浄the solution washed with water and saturated sodium bicarbonate (150 mL each)
11. 11
    乾燥dried (Na2SO4)
12. 12
    濃縮concentrated
13. 13
    workup.DISSOLUTIONThe residue was dissolved in minimum methylene chloride
14. 14
    洗浄eluted with 55:30:15 heptane/methylene chloride/ethyl acetate

実験手順

An ice-cooled (3° C.) stirred solution of N-boc-glycine, allyl ester (6.46 g, 30 mmol) in anhydrous tetrahydrofuran (60 mL) under nitrogen was treated with 1N lithium bis(trimethylsilylamide)/tetrahydrofuran (33 mL, 33 mmol) at a rate to keep pot temperature below 10° C., then stirred at 3° C. for 15 min and cooled (−40° C.). A solution of allyl acrylate (4.45 mL, 35 mmol) in anhydrous tetrahydrofuran (25 mL) was added dropwise, and the mixture allowed to reach room temperature, stirred 1 h, and refluxed for 2 h. The mixture was cooled to room temperature, quenched with glacial acetic acid (2.5 mL), and concentrated. The residual oil was dissolved in methylene chloride (300 mL) and the solution washed with water and saturated sodium bicarbonate (150 mL each), dried (Na2SO4), and concentrated. The residue was dissolved in minimum methylene chloride and loaded onto a silica gel column (350 mL volume) and eluted with 55:30:15 heptane/methylene chloride/ethyl acetate to afford 3-allyl 1-tert-butyl 4-oxopyrrolidine-1,3-dicarboxylate (5.07 g, 63%) as a colorless oil. NMR (CDCl3): δ 5.85-6.00 (m, 1 H), 5.20-5.40 (m, 2 H), 4.60-4.75 (m, 2 H), 4.20 (m, 1 H), 3.95-4.10 (m, 1 H), 3.87 (d, J=6.5 Hz, 1 H), 3.62 (t, J=8 Hz, 1 H), 1.48 (s, 9 H). MS (m+1): 270.4; MS (m−bu+1): 214.2.

出典