Reaktion #44874

Reaktionsgleichung

3-isopropyl-2-oxo-N-(piperidin-4-ylmethyl)-2,3-dihydro-1H-benzimidazole-1-carboxamide

3-Isopropyl-2-oxo-N-(piperidin-4-ylmethyl)-2,3-dihydro-1H -benzimidazole-1-carboxamide

tert-butyl acrylate

→

title compound

Ausbeute 16.0%

tert-butyl 3-[4-({[(3-isopropyl-2-oxo-2,3-dihydro-1H -benzimidazol-1-yl)carbonyl]amino}methyl)piperidin-1-yl]propanoate

Ausbeute 16.0%

Lösungsmittel

NaHCO3

THF

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturwas refluxed for 18 h
2. 2
   TemperaturAfter cooling
3. 3
   Extraktionextracted with CH2Cl2 (100 mL) for three times
4. 4
   TrocknenThe combined extracts were dried over Na2SO4
5. 5
   Filtrationfiltered
6. 6
   Einengenconcentrated
7. 7
   SonstigeThe residue was chromatographed on a column of silica gel
8. 8
   Wascheneluted with MeOH/CH2Cl2 (1:20→1:10)
9. 9
   WaschenNH-silica gel eluted with EtOAc/hexane (1:5→1:2)

Vorschrift

A mixture of 3-isopropyl-2-oxo-N-(piperidin-4-ylmethyl)-2,3-dihydro-1H-benzimidazole-1-carboxamide (0.50 g, 1.58 mmol, Step 2), tert-butyl acrylate (0.340 mL, 2.37 mmol) and iPrNEt (0.275 mL, 2.37 mmol) in THF (20 mL) was refluxed for 18 h. After cooling, the reaction mixture was diluted with sat. NaHCO3 aq. (100 mL), extracted with CH2Cl2 (100 mL) for three times. The combined extracts were dried over Na2SO4, filtered and concentrated. The residue was chromatographed on a column of silica gel eluted with MeOH/CH2Cl2 (1:20→1:10) and then NH-silica gel eluted with EtOAc/hexane (1:5→1:2) to give 0.111 g (16%) of title compound as colorless syrup.

Quelle