反応 #1416

反応方程式

methyl iodide

Cesium carbonate

N2 [(1,1-dimethylethoxy)carbonyl]-N6 -[(phenylmethoxy)carbonyl]-L-lysine

water methanol

→

N2 [(1,1-Dimethylethoxy)carbonyl]-N6 -[(phenylmethoxy)carbonyl]-L-lysine, methyl ester

溶媒

—

hexanes

ethyl acetate

ethyl acetate

反応条件

後処理

1. 1
   その他the residual water removed azeotropically with acetonitrile (3×)
2. 2
   その他The resulting oil was dried in vacuo
3. 3
   workup.DISSOLUTIONdissolved in dry dimethyl-formamide
4. 4
   洗浄washed successively with water (2×25 ml.), saturated sodium bicarbonate (25 ml.) and brine (25 ml.)
5. 5
   乾燥The organic phase was dried (anhydrous magnesium sulfate)
6. 6
   ろ過filtered
7. 7
   その他evaporated to dryness
8. 8
   その他dried in vacuo
9. 9
   その他to give 10.11 g

実験手順

Cesium carbonate (4.28 g., 13.1 moles) was added to a mixture of N2 -[(1,1-dimethylethoxy)carbonyl]-N6 -[(phenylmethoxy)carbonyl]-L-lysine (10 g., 26.3 moles) and 20% water-methanol (60 ml.). The solution became homogeneous within 5 minutes so the solvent was stripped and the residual water removed azeotropically with acetonitrile (3×). The resulting oil was dried in vacuo, dissolved in dry dimethyl-formamide and treated with methyl iodide (3.2 ml., 2.0 eq.). The reaction mixture was stirred at room temperature for 1.5 hours under argon, diluted with ethyl acetate (200 ml.) and washed successively with water (2×25 ml.), saturated sodium bicarbonate (25 ml.) and brine (25 ml.). The organic phase was dried (anhydrous magnesium sulfate), filtered, evaporated to dryness and dried in vacuo to give 10.11 g., of product as a light yellow syrup; Rf =0.30 (ethyl acetate:hexanes, 1:2).

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