反応 #324378

反応方程式

5-[4-(tert-butyldimethylsilyloxy)phenyl]-3-phenylpyrazin-2-amine

5-[4-(tert-Butyldimethylsilyloxy)phenyl]-3-phenylpyrazin-2-amine

2-[4-(tert-butyldimethylsilyloxy)phenyl]acetyl chloride

water

→

Compound 11a

収率 75.4%

2-[4-(tert-Butyldimethylsilyloxy)phenyl]-N-{5-[4-(tert-butyldimethylsilyloxy)phenyl]-3-phenylpyrazin-2-yl}acetamide

収率 75.4%

溶媒

pyridine

反応条件

後処理

1. 1
   その他prepared above at 0° C.
2. 2
   温度the mixture was heated
3. 3
   温度After cooling to room temperature
4. 4
   抽出the product was extracted with ethyl acetate (100 mL×3)
5. 5
   抽出The combined organic extract
6. 6
   洗浄was washed successively with water (200 mL) and brine (200 mL)
7. 7
   乾燥by drying over anhydrous sodium sulfate
8. 8
   ろ過After filtration and concentration under reduced pressure
9. 9
   その他the residue was purified by column chromatography (silica gel 50 g, n-hexane/ethyl acetate=4/1)

実験手順

Under an argon atmosphere, to a mixture of 5-[4-(tert-butyldimethylsilyloxy)phenyl]-3-phenylpyrazin-2-amine (7a) (504 mg, 1.33 mmol) and 4-(dimethylamino)pyridine (16.3 mg, 133 μmol) dissolved in anhydrous pyridine (20 mL) was added 2-[4-(tert-butyldimethylsilyloxy)phenyl]acetyl chloride (10) prepared above at 0° C. and the mixture was heated with stirring at 50° C. for 18 hours. After cooling to room temperature, to this was added water and the product was extracted with ethyl acetate (100 mL×3). The combined organic extract was washed successively with water (200 mL) and brine (200 mL), followed by drying over anhydrous sodium sulfate. After filtration and concentration under reduced pressure, the residue was purified by column chromatography (silica gel 50 g, n-hexane/ethyl acetate=4/1) to give Compound 11a (630 mg, 1.01 mmol, 75.4%) as a yellow foamy solid. Rf=0.33 (n-hexane/diethyl ether=2/3); 1H NMR (400 MHz, DMSO-d6) δ 0.18 (s, 6H), 0.23 (s, 6H), 0.94 (s, 9H), 0.96 (s, 9H), 3.47 (s, 2H), 6.72-6.79 (AA′BB′, 2H), 6.96-7.02 (AA′BB′, 2H), 7.03-7.09 (AA′BB′, 2H), 7.29-7.39 (m, 3H), 7.66-7.74 (m, 2H), 8.05-8.12 (AA′BB′, 2H), 8.98 (s, 1H), 10.54 (s, 1H); 13C NMR (75.5 MHz, DMSO-d6) δ −4.6 (4C), 17.9, 18.0, 25.50 (3C), 25.54 (3C), 41.7, 119.5 (2C), 120.3 (2C), 127.8 (2C), 127.9, 128.0 (2C), 128.2 (2C), 128.5, 128.9, 130.3 (2C), 130.5, 137.6, 142.8, 147.6, 148.0, 153.8, 156.7, 169.3; IR (KBr, cm−1) 523, 694, 781, 804, 839, 914, 1020, 1070, 1086, 1105, 1169, 1263, 1371, 1416, 1510, 1605, 1672, 2857, 2886, 2930, 2955, 3040, 3059, 3233; HRMS (ESI+)/z 648.3043 ([M+Na]+, C36H47N3NaO3Si2+ requires 648.3048).

出典