تفاعل #59159

معادلة التفاعل

HCl

isoamyl nitrite

2-amino-4-methylbenzothiazole

→

2-chloro-4-methyl-1,3-benzothiazole

المردود 71.0%

المذيبات

acetonitrile

—

tri(ethylene glycol)dimethyl ether

ظروف التفاعل

المعالجة

1. 1
   workup.STIRRINGThe reaction mixture was stirred at rt for 10 minutes
2. 2
   درجة الحرارةheated at 50° C. for 2.5 h
3. 3
   درجة الحرارةThe reaction mixture was cooled to rt
4. 4
   استخلاصThe solution was extracted with EtOAc
5. 5
   غسيلThe organic layer was washed with HCl (1.0 M), water, brine
6. 6
   ترشيحfiltered
7. 7
   تركيزconcentrated in vacuo
8. 8
   أخرىThe residue was purified by flash chromatography (Biotage Flash 40M)

الإجراء التجريبي

To a solution containing copper chloride (II) (1.96 g, 14.61 mmol) and tri(ethylene glycol) dimethyl ether (6 mL) in acetonitrile (100 mL) was added isoamyl nitrite (2.14 g, 18.27 mmol), and the reaction mixture was stirred at rt for 30 minutes. To this suspension was added dropwise a solution of 2-amino-4-methylbenzothiazole (2.0 g, 12.18 mmol) in tri(ethylene glycol)dimethyl ether (10 mL). The reaction mixture was stirred at rt for 10 minutes, and then heated at 50° C. for 2.5 h. The reaction mixture was cooled to rt, and then poured cautiously into cold aqueous 6 M HCl (400 mL). The solution was extracted with EtOAc. The organic layer was washed with HCl (1.0 M), water, brine, filtered and concentrated in vacuo. The residue was purified by flash chromatography (Biotage Flash 40M) using 5% ethyl acetate in hexane to afford 2-chloro-4-methyl-1,3-benzothiazole (1.6 g, 71%). 1H NMR (400 MHz, CD2Cl2) δ 2.70 (s, 3H), 7.32 (m, 2H), 7.64 (m, 1H).

المصدر