تفاعل #324412

معادلة التفاعل

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

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

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

water

→

Compound 11r

المردود 45.8%

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

المردود 45.8%

المذيبات

pyridine

ظروف التفاعل

المعالجة

1. 1
   أخرىprepared above at 0° C.
2. 2
   درجة الحرارةthe mixture was heated
3. 3
   درجة الحرارةAfter cooling to room temperature
4. 4
   استخلاصthe product was extracted with ethyl acetate (100 mL×3)
5. 5
   استخلاصThe combined organic extract
6. 6
   غسيلwas washed successively with water (200 mL) and brine (200 mL)
7. 7
   تجفيفby drying over anhydrous sodium sulfate
8. 8
   ترشيحAfter filtration and concentration under reduced pressure
9. 9
   أخرىthe residue was purified by column chromatography (silica gel 50 g, n-hexane/ethyl acetate=3/1)

الإجراء التجريبي

Under an argon atmosphere, to a mixture of 5-[4-(tert-butyldimethylsilyloxy)phenyl]-3-phenethylpyrazin-2-amine (7r) (403 mg, 994 μmol) and 4-(dimethylamino)pyridine (19.6 mg, 160 μmol) dissolved in anhydrous pyridine (15 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 20 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=3/1) to give Compound 11r (298 mg, 455 μmol, 45.8%) as a yellow oily substance. Rf=0.44 (n-hexane/ethyl acetate=2/1); 1H NMR (400 MHz, DMSO-d6) δ 0.12 (s, 6H), 0.20 (s, 6H), 0.91 (s, 9H), 0.93 (s, 9H), 2.83 (t, 1H, J=8.4 Hz), 2.94 (t, 1H, J=8.4 Hz), 3.59 (s, 2H), 6.72-6.79 (AA′BB′, 2H), 6.92-7.00 (AA′BB′, 2H), 7.01-7.07 (AA′BB′, 2H), 7.07-7.15 (m, 1H), 7.16-7.24 (m, 4H), 7.97-8.05 (AA′BB′, 2H), 8.81 (s, 1H), 10.44 (s, 1H); 13C NMR (67.8 MHz, DMSO-d6) δ −4.5 (2C), −4.6 (2C), 17.9, 18.0, 25.5 (6C), 32.8, 34.7, 41.7, 119.6 (2C), 120.3 (2C), 125.7, 128.1 (2C), 128.2 (4C), 128.5, 129.1, 130.2 (2C), 130.3, 136.6, 141.4, 143.8, 147.9, 150.6, 153.8, 156.6, 170.3; IR (KBr, cm−1) 525, 698, 781, 839, 914, 1007, 1169, 1258, 1362, 1416, 1443, 1510, 1605, 1661, 2857, 2930, 2955, 3225.

المصدر