Reaction #607492

Reaction equation

137m

7,7-dimethyl-1-oxo-2,3,4,6,7,8-hexahydro-1H-pyrido[3,4-b]pyrrolizine-9-carboxylic acid

phenanthroline

quinoline

HCl

→

7,7-dimethyl-2,3,4,6,7,8-hexahydro-1H-pyrido[3,4-b]pyrrolizin-1-one

Yield 61.0%

Solvents

NMP

Water

Conditions

Workup

1. 1
   OtherThe reaction mixture was microwaved at 200° C. for 3 h
2. 2
   Extractionextracted with EA (50 mL×3)
3. 3
   DryingThe combined organic extracts were dried over anhydrous sodium sulfate
4. 4
   Filtrationfiltered
5. 5
   Concentrationconcentrated under reduced pressure
6. 6
   OtherThe residue was purified by silica gel chromatography (DCM/MeOH=10/1)

Procedure

A microwave vial was charged with 137m (900 mg, 3.63 mmol), Cu2O (26 mg, 0.18 mmol), phenanthroline (66 mg, 0.36 mmol), quinoline (3 g, 23 mmol) and NMP (8 mL). The reaction mixture was microwaved at 200° C. for 3 h. See FIG. 2. Water was added and the mixture was neutralized to pH 7 by addition of 1N HCl and extracted with EA (50 mL×3). The combined organic extracts were dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure. The residue was purified by silica gel chromatography (DCM/MeOH=10/1) to give 7,7-dimethyl-2,3,4,6,7,8-hexahydro-1H-pyrido[3,4-b]pyrrolizin-1-one 137n (450 mg, 61%) as a white solid. 1H NMR (400 MHz, CDCl3) δ 6.18 (t, J=1.2 Hz, 1H), 5.16 (s, 1H), 3.57 (s, 4H), 2.76 (t, J=6.9 Hz, 2H), 2.64 (d, J=1.1 Hz, 2H), 1.25 (s, 6H); MS-ESI [M+H]+=205.1.

Source