反応 #1999

反応方程式

benzyl alcohol

diphenylphosphoryl azide

2,2-dimethylbutanedioic acid-4-methyl ester

triethylamine

→

product

収率 75.1%

3-Benzyloxycarbonylamino-3-methylbutanoic acid, methyl ester

収率 75.1%

溶媒

benzene

反応条件

後処理

1. 1
   温度The mixture was heated under nitrogen
2. 2
   温度at reflux for 45 minutes
3. 3
   温度refluxing
4. 4
   温度The mixture was cooled
5. 5
   ろ過filtered
6. 6
   濃縮the filtrate concentrated to a minimum volume under vacuum
7. 7
   workup.DISSOLUTIONThe residue was redissolved in 250 mL of ethyl acetate
8. 8
   洗浄washed with water, saturated aqueous sodium bicarbonate (2×) and brine
9. 9
   その他The organic layer was removed
10. 10
    乾燥dried over magnesium sulfate
11. 11
    ろ過filtered
12. 12
    濃縮the filtrate concentrated to a minimum volume under vacuum
13. 13
    その他The crude product was purified by medium pressure liquid chromatography on silica
14. 14
    洗浄eluting with hexane/ethyl acetate (4:1)

実験手順

To 14.7 g (91.8 mmol) of 2,2-dimethylbutanedioic acid-4-methyl ester in 150 mL of benzene was added 13 mL of triethylamine (9.4 g, 93 mmol) followed by 21.8 mL of diphenylphosphoryl azide (27.8 g, 101 mmol). The mixture was heated under nitrogen at reflux for 45 minutes then 19 mL (19.9 g, 184 mmol) of benzyl alcohol was added and refluxing continued for 16 hours. The mixture was cooled, filtered and the filtrate concentrated to a minimum volume under vacuum. The residue was redissolved in 250 mL of ethyl acetate, washed with water, saturated aqueous sodium bicarbonate (2×) and brine. The organic layer was removed, dried over magnesium sulfate, filtered and the filtrate concentrated to a minimum volume under vacuum. The crude product was purified by medium pressure liquid chromatography on silica, eluting with hexane/ethyl acetate (4:1), to afford 18.27 g (68.9 mmol, 75%) of the product.

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