Реакция #1119

Уравнение реакции

dichloroethane

sodium triacetoxyborohydride

acetic acid

sodium hydrogen carbonate

4-phenylcyclohexanone

triethyl orthoformate

2-ethyl-3-bromo-4-aminopyridine

→

2-Ethyl-3-bromo-4-(cis-4-phenylcyclohexylamino)pyridine

Растворители

ethanol

Условия реакции

Обработка

1. 1
   Температураis heated at 135°-140° C. for 3.5-4 hours with simultaneous removal of the low-boiling components by distillation
2. 2
   ТемператураIt is then cooled
3. 3
   Температураit is heated at 50°-60° C. for 3 hours
4. 4
   Температураthe reaction mixture is then cooled
5. 5
   Другоеthe 1,2-dichloroethane is evaporated
6. 6
   Экстракцияthe reaction product is extracted from the aqueous phase
7. 7
   ДругоеPurification

Методика

3.48 g (20 mmol) of 4-phenylcyclohexanone in 3.3 ml of ethanol are treated with 3.3 ml of triethyl orthoformate and 2 drops of boron trifluoride etherate and warmed at 50° C. for 30 min. After addition of 2.01 g (10mmol) of 2-ethyl-3-bromo-4-aminopyridine the reaction mixture is heated at 135°-140° C. for 3.5-4 hours with simultaneous removal of the low-boiling components by distillation. It is then cooled, 40 ml of dichloroethane, 3.18 g (15 mmol) of sodium triacetoxyborohydride and 0.57 ml (10 mmol) of glacial acetic acid are added, and it is heated at 50°-60° C. for 3 hours; the reaction mixture is then cooled, saturated aqueous sodium hydrogen carbonate solution is added, the 1,2-dichloroethane is evaporated and the reaction product is extracted from the aqueous phase using ethyl acetate. Purification is carried out by column chromatography. Yield: 1.46 g (41%); RF =0.59 (ethyl acetate)

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