تفاعل #324378

معادلة التفاعل

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

المردود 75.4%

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

المردود 75.4%

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=4/1)

الإجراء التجريبي

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).

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