Реакция #51208

Уравнение реакции

5-acetyl-2,3-dihydrobenzo[b]furan

methyl cyanoacetate

benzylamine

acetic acid

→

title product

Выход 60.1%

Methyl-(2E)-2-cyano-3-(2,3-dihydro-1-benzofuran-5-yl)-2-butenoate

Выход 60.1%

Растворители

toluene

Условия реакции

Обработка

1. 1
   Температураthe whole refluxed in a Dean-Stark apparatus for 16 h
2. 2
   ТемператураThe reaction mixture was cooled
3. 3
   Промывкаwashed with 2N HCl (30 ml), NaHCO3 (30 ml), brine (30 ml)
4. 4
   Сушкаdried (MgSO4)
5. 5
   Другоеevaporated to a yellow residue
6. 6
   ДругоеThis residue was purified by column chromatography

Методика

To a stirred solution of 5-acetyl-2,3-dihydrobenzo[b]furan (Aldrich) (1 g, 6.17 mmol) in toluene (60 ml) was added methyl cyanoacetate (0.60 ml, 6.78 mmol), benzylamine (0.07 ml, 0.61 mmol) and acetic acid (0.3 ml, 5.3 mmol) and the whole refluxed in a Dean-Stark apparatus for 16 h. The reaction mixture was cooled, washed with 2N HCl (30 ml), NaHCO3 (30 ml), brine (30 ml), dried (MgSO4) and evaporated to a yellow residue. This residue was purified by column chromatography using 15-20% EtOAc in pentane as eluant to provide the title product (902 mg, 60%); 1HNMR (400 MHz, CDCl3) δ: 2.65 (s, 3H), 3.25 (t, 2H), 3.9 (s, 3H), 4.6 (t, 2H), 6.8 (d, 1H), 7.25 (d, 1H), 7.8 (s, 1H); LRMS: M+NH4+, 261. (ES+).

Источник