반응 #1729

반응 방정식

3-hexyl-5,5,8,8-tetramethyl-5,6,7,8-tetrahydro-naphthalen-2-yl-carboxylic acid

benzyl 6-hydroxy-nicotinate

dicyclohexylcarbodiimide

→

benzyl 6-(3-hexyl-5,5,8,8-tetramethyl-5,6,7,8-tetrahydro-naphthalen-2-yl-carbonyloxy)-nicotinate

수율 57.0%

용매

methylene chloride

methylene chloride

반응 조건

후처리

1. 1
   workup.ADDITIONpoured into ice-cold aqueous ammonium chloride solution
2. 2
   추출extracted several times with ether
3. 3
   세척washed with water
4. 4
   건조dried over sodium sulfate
5. 5
   기타evaporated
6. 6
   여과The crude product, for the most part crystalline, was filtered over silica gel (eluent hexane/ethyl acetate=9:1)
7. 7
   기타recrystallized from hexane
8. 8
   기타crystallization of the mother liquor

실험 절차

6 g of 3-hexyl-5,5,8,8-tetramethyl-5,6,7,8-tetrahydro-naphthalen-2-yl-carboxylic acid were dissolved in 180 ml of methylene chloride. After the addition of a solution of 4.8 g of benzyl 6-hydroxy-nicotinate in 160 ml of methylene chloride and of 2.3 g of 4-dimethylaminopyridine, the solution was cooled to 0° C. and treated with 4.4 g of dicyclohexylcarbodiimide. The reaction mixture was stirred at 0° C. for 1 hour and at room temperature for 2 hours, thereafter poured into ice-cold aqueous ammonium chloride solution, extracted several times with ether, washed with water, dried over sodium sulfate and evaporated. The crude product, for the most part crystalline, was filtered over silica gel (eluent hexane/ethyl acetate=9:1) and recrystallized from hexane. After repeated crystallization of the mother liquor there were obtained all together 5.7 g of benzyl 6-(3-hexyl-5,5,8,8-tetramethyl-5,6,7,8-tetrahydro-naphthalen-2-yl-carbonyloxy)-nicotinate in colorless crystals, m.p. 94°-95° C.

출처