تفاعل #1293

معادلة التفاعل

cesium carbonate

(S)-2-phthalimido-6-hydroxyhexanoic acid

benzyl bromide

→

title product

(S)-2-Phthalimido-6-hydroxyhexanoic acid, phenylmethyl ester

المذيبات

dimethylformamide

ظروف التفاعل

المعالجة

1. 1
   أخرىthe mixture was partitioned between ethyl acetate and water
2. 2
   استخلاصThe organic extract
3. 3
   غسيلwas washed with water (twice) and brine
4. 4
   تجفيفdried (sodium sulfate)
5. 5
   ترشيحfiltered
6. 6
   أخرىto give an oil
7. 7
   أخرىchromatographed (Merck silica gel, 6/4-ethyl acetate/hexane)
8. 8
   أخرىto give essentially pure product as a solid
9. 9
   أخرىRecrystallization from ethyl acetate/hexane
10. 10
    أخرىgave 7.173 g

الإجراء التجريبي

A slurry of cesium carbonate (3.819 g, 11.7 mmol.) and (S)-2-phthalimido-6-hydroxyhexanoic acid (6.00 g, 21.6 mmol.) in dimethylformamide (60 ml.) was treated with benzyl bromide (3.30 ml., 4.75 g., 27.7 mmol.). After stirring at room temperature for 2 hours, the mixture was partitioned between ethyl acetate and water. The organic extract was washed with water (twice) and brine, then dried (sodium sulfate), filtered and stripped to give an oil. The oil was flash chromatographed (Merck silica gel, 6/4-ethyl acetate/hexane) to give essentially pure product as a solid. Recrystallization from ethyl acetate/hexane gave 7.173 g. (1st crop) and 394 mg. (2nd crop) for a total of 7.567 g. of pure title product; m.p. 106°-108.5° C.; [α]D =-27-5° (c=1.5, methanol). TLC (75/25 ethyl acetate/hexanes) Rf =0.43.

المصدر