تفاعل #1004568

معادلة التفاعل

cyclohexanecarboxamide

Lawesson's reagent

ethyl 2-chloro-3-oxobutanate

→

ethyl 2-cyclohexyl-4-methylthiazole-5-carboxylate

المردود 184.2%

المذيبات

tetrahydrofuran

ظروف التفاعل

المعالجة

1. 1
   درجة الحرارةby heating
2. 2
   درجة الحرارةunder refluxing for 3 hours
3. 3
   أخرىThe reaction liquid
4. 4
   درجة الحرارةheating
5. 5
   درجة الحرارةunder refluxing for further 3 hours
6. 6
   أخرىThe reaction liquid
7. 7
   استخلاصextracted with diethyl ether
8. 8
   غسيلThe organic layer was washed with water, dilute hydrochloric acid
9. 9
   تجفيفby drying over anhydrous magnesium sulfate
10. 10
    تركيزconcentrating under reduced pressure
11. 11
    أخرىThe residue was purified with silica gel column chromatography (ethyl acetate:hexane=1:5)

الإجراء التجريبي

To 90 ml of tetrahydrofuran, 11.1 g (87 mmol) of cyclohexanecarboxamide and 17.6 g (43.5 mmol) of Lawesson's reagent were suspended, followed by heating under refluxing for 3 hours. The reaction liquid was cooled to room temperature, followed by adding 14.4 g (87 mmol) of ethyl 2-chloro-3-oxobutanate and heating under refluxing for further 3 hours. The reaction liquid was poured into ice water and extracted with diethyl ether. The organic layer was washed with water, dilute hydrochloric acid, an aqueous solution of sodium carbonate and saturated saline solution in this order, followed by drying over anhydrous magnesium sulfate and concentrating under reduced pressure. The residue was purified with silica gel column chromatography (ethyl acetate:hexane=1:5) to obtain 20.3 g (yield: 92%) of ethyl 2-cyclohexyl-4-methylthiazole-5-carboxylate.

المصدر