反応 #219807

反応方程式

(S)-2-Methyl-propane-2-sulfinic acid ((3S)-1,3-dimethyl-pentylidene)-amide

diisopropylamine

butyllithium

Methyl acetate

→

titled compound

収率 62.1%

(3S,5S)-3,5-Dimethyl-3-((S)-2-methyl-propane-2-sulfinylamino)-heptanoic acid methyl ester

収率 62.1%

溶媒

THF

THF

THF

THF

反応条件

後処理

1. 1
   その他at −78° C.
2. 2
   温度subsequently cooled down to −78° C
3. 3
   workup.STIRRINGAfter Stirring for 20 minutes
4. 4
   workup.STIRRINGthe resulting mixture was stirred at −78° C. for 20 minutes
5. 5
   workup.STIRRINGThe mixture was stirred at −78° C. overnight
6. 6
   その他The reaction was quenched by NH4Cl solution (50 mL)
7. 7
   ろ過The mixture was filtered
8. 8
   抽出The filtrate was extracted by EtOAc (3×70 mL)
9. 9
   その他the residue was purified by a silica gel column (Hexane/EtOAc 1:1)

実験手順

To a solution of diisopropylamine (3.1 mL, 22.2 mmol) in THF (40 mL) at −78° C. was slowly added butyllithium (14.4 mL, 1.6 M, 23 mmol). The mixture was stirred at 0° C. for 25 minutes and subsequently cooled down to −78° C. Methyl acetate (1.76 mL, 22.2 mmol) in THF (7 mL) was added. After Stirring for 20 minutes, chlorotitaniumtriisopropoxide (11 mL, 46.2 mmol) in THF (10 mL) was added and the resulting mixture was stirred at −78° C. for 20 minutes. (S)-2-Methyl-propane-2-sulfinic acid ((3S)-1,3-dimethyl-pentylidene)-amide (1.9 g, 8.9 mmol) in THF (10 mL) was added. The mixture was stirred at −78° C. overnight. The reaction was quenched by NH4Cl solution (50 mL). The mixture was filtered. The filtrate was extracted by EtOAc (3×70 mL). The EtOAc phase was reduced under reduce pressure and the residue was purified by a silica gel column (Hexane/EtOAc 1:1) to give the titled compound (1.61 g, 62% yield) as a colorless oil: 1H NMR (CDCl3) δ 3.64 (s, 3H), 2.60 (m, 2H), 1.47 (m, 2H), 1.44 (m, 1H), 1.36 (s, 3H), 1.27 (m, 2H), 1.19 (s, 9H), 0.90 (d, J=6.4 Hz, 3H), 0.81 (t, J=7.6 Hz, 3H); MS (APCI) (M+1)+ 292.2.

出典