反应 #632034

反应方程式

compound ( 27 )

1-Hydroxy-(3S,4S)-2,5-Dioxo-3,4-dibenzoyloxypyrrolidine

thiocarbonate

O-(1-Isobutanoyloxyisobutoxy) S-Methyl Thiocarbonate

peracetic acid

peracetic acid

→

title compound ( 25 )

收率 25.7%

(1R)-1-[((3S,4S)-2,5-Dioxo-3,4-dibenzoyloxypyrrolidinyl)-oxycarbonyloxy]-2-methylpropyl 2-methylpropanoate

收率 25.7%

溶剂

dichloromethane

acetic acid

反应条件

后处理

1. 1
   workup.ADDITIONAfter the addition
2. 2
   过滤The resulting white precipitate was filtered
3. 3
   洗涤washed successively with water
4. 4
   workup.ADDITIONa mixture of ether and hexane (1:2)
5. 5
   其他dried under vacuum
6. 6
   其他to afford the crude title compound
7. 7
   其他This product was crystallized once from a mixture of ethyl acetate and hexane (1:1)

实验过程

To a stirred solution of compound (27) (35 g, 98.6 mmol) and thiocarbonate (11) (34.6 g, 148 mmol) in dichloromethane at 0° C. was dropwise added a 32% solution of peracetic acid (300 mmol) in acetic acid over 2 h. The reaction temperature was kept below 35° C. during the addition of peracetic acid. After the addition was complete, the reaction mixture was stirred overnight at room temperature. The resulting white precipitate was filtered and washed successively with water, and a mixture of ether and hexane (1:2), then dried under vacuum to afford the crude title compound. This product was crystallized once from a mixture of ethyl acetate and hexane (1:1) to afford the title compound (25) (13.7 g, 25% yield). The diastereomeric purity of the product was determined to be 98.4% d.e. by HPLC using a chiral column. 1H NMR (CDCl3, 400 MHz): δ 1.06 (d, 6H), 1.22 (d, 3H), 1.22 (d, 3H), 2.20 (m, 1H), 2.64 (hept. 1H), 6.01 (br. s, 2H), 6.64 (d, 1H), 7.47 (m, 4H), 7.63 (m, 2H), 8.07 (m, 4H).

来源