反応 #1729

反応方程式

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

収率 57.0%

溶媒

methylene chloride

methylene chloride

反応条件

後処理

1. 1
   workup.ADDITIONpoured into ice-cold aqueous ammonium chloride solution
2. 2
   抽出extracted several times with ether
3. 3
   洗浄washed with water
4. 4
   乾燥dried over sodium sulfate
5. 5
   その他evaporated
6. 6
   ろ過The crude product, for the most part crystalline, was filtered over silica gel (eluent hexane/ethyl acetate=9:1)
7. 7
   その他recrystallized from hexane
8. 8
   その他crystallization of the mother liquor

実験手順

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.

出典