反応 #10273

反応方程式

4-benzyl-piperazine-1-carboxylic acid tert-butyl ester

tetramethylethylenediamine

2-(bromomethyl)naphthalene

sec-butyllithium

→

4-benzyl-2-(naphthalen-2-ylmethyl)piperazine-1-carboxylic acid tert-butyl ester

溶媒

diethylether

diethylether

反応条件

後処理

1. 1
   workup.ADDITIONafter complete addition the solution
2. 2
   温度was slowly warmed to −10° C., at which temperature the mixture
3. 3
   その他was recooled to −70° C.
4. 4
   workup.STIRRINGstirring
5. 5
   その他continued at −70° C.
6. 6
   workup.WAITwas continued for one hour
7. 7
   workup.STIRRINGThe resulting mixture was stirred
8. 8
   workup.WAITto come to room temperature overnight
9. 9
   その他partitioned between saturated ammonium chloride (aq) and ethyl acetate
10. 10
    乾燥The organic layer was dried over magnesium sulphate
11. 11
    ろ過filtered
12. 12
    濃縮concentrated in vacuo
13. 13
    その他The residue was purified by flash chromatography (SiO2, CH2Cl2/MeOH 99/1)

実験手順

To a solution of 4-benzyl-piperazine-1-carboxylic acid tert-butyl ester (2 g) in diethylether (35 mL) was added tetramethylethylenediamine (1.4 mL). The resulting mixture was cooled to −70° C. and sec-butyllithium (7 mL of a 1.3 M solution) was added dropwise, after complete addition the solution was slowly warmed to −10° C., at which temperature the mixture was stirred for one hour. Subsequently, the mixture was recooled to −70° C.; then a solution of 2-(bromomethyl)naphthalene (2 g) in diethylether was added dropwise and stirring continued at −70° C. was continued for one hour. The resulting mixture was stirred and allowed to come to room temperature overnight, then partitioned between saturated ammonium chloride (aq) and ethyl acetate. The organic layer was dried over magnesium sulphate, filtered, and concentrated in vacuo. The residue was purified by flash chromatography (SiO2, CH2Cl2/MeOH 99/1) to afford 4-benzyl-2-(naphthalen-2-ylmethyl)piperazine-1-carboxylic acid tert-butyl ester as an oil. 0.8 g (27 %) Rf 0.47 (CH2Cl2/MeOH 99/1), MH+ 417.

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