Réaction #568256

Équation de réaction

4-oxo-1,4,5,6,7,8-hexahydro-cyclohepta(b)pyrrole-3-carboxylic acid ethyl ester

3-amino-prop-2-enal

ammonium acetate

→

3,4,5,6-tetrahydro-3,10-diaza-benzo[e]azulene-1-carboxylic acid ethyl ester

Rendement 20.0%

Solvants

NaHCO3

triethylamine

dichloromethane

Conditions de réaction

Traitement

1. 1
   TempératureIt is cooled to room temperature
2. 2
   AutreLayers are separated
3. 3
   Extractionthe aqueous phase is extracted with 4:1 DCM/2-propanol (4×100 mL)
4. 4
   SéchageCombined organic layers are dried (Na2SO4)
5. 5
   Autreevaporated
6. 6
   LavageFlash Chromatography on silica gel, eluting with EtOAc:triethylamine (20:1)

Mode opératoire

A mixture of 4-oxo-1,4,5,6,7,8-hexahydro-cyclohepta(b)pyrrole-3-carboxylic acid ethyl ester (7.0 g, 31.67 mmol), 3-amino-prop-2-enal (3.37 g, 47.5 mmol) and ammonium acetate (365 mg, 4.75 mmol) in triethylamine (7 mL) is heated at 110° C. for 4 h. It is cooled to room temperature and the solid residue is dissolved in 100 mL dichloromethane and 100 mL sat. NaHCO3 solution. Layers are separated and the aqueous phase is extracted with 4:1 DCM/2-propanol (4×100 mL). Combined organic layers are dried (Na2SO4) and evaporated. Flash Chromatography on silica gel, eluting with EtOAc:triethylamine (20:1), provides 3,4,5,6-tetrahydro-3,10-diaza-benzo[e]azulene-1-carboxylic acid ethyl ester (1.6 g, 20%) as off-white solid. 1H NMR (400 MHz, CD3OD) δ1.247 (3H, t), 2.227 (2H, m), 2.631 (4H, m), 4.197 (2H, q), 7.170 (1H, m), 7.405 (1H, s), 7.686 (1H, d), 8.375 (1H, d). MS (ES+) 257 (M+1)

Source