Reaktion #511521

Reaktionsgleichung

water

1-pyrrolidino-1-cyclopentene

(R)-propyl 2-acetamido-3-chloropropanoate

dimethylethylamine

→

propyl 2-acetamido-3-(2-oxocyclopentyl)propanoate

Ausbeute 87.0%

Lösungsmittel

acetonitrile

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigewas kept at 20° C.
2. 2
   SonstigeThe homogeneous reaction
3. 3
   workup.STIRRINGthe reaction was further stirred for 2.5 h
4. 4
   SonstigeThe solvents were removed in vacuo at 50° C.
5. 5
   Sonstigethe residual oil was purified by silica gel flash chromatography

Vorschrift

(R)-propyl 2-acetamido-3-chloropropanoate (2.50 g, 12.0 mmol) was dissolved in acetonitrile (25 mL) and 1-pyrrolidino-1-cyclopentene (2.27 mL, 2.14 g, 15.6 mmol) was added. While the reaction was kept at 20° C., dimethylethylamine (1.70 mL, 1.14 g, 15.6 mmol) was added via an addition funnel during 10 min. The homogeneous reaction was stirred at 20° C. for 21 h. Then, water (0.50 mL) was added and the reaction was further stirred for 2.5 h. The solvents were removed in vacuo at 50° C. and the residual oil was purified by silica gel flash chromatography using an EtOAc:petroleum benzene gradient. The product is a yellowish oil. Weight 2.67 g, approx. 87% yield (two diastereomers). 1H NMR: (CDCl3, 300 MHz): δ 6.62 (br d, 0.5H), 6.38 (br d, 0.5H), 4.61-4.49 (m, 1H), 4.05-4.00 (m, 2H), 2.38-1.92 (m, 8H), 1.80-1.47 (m, 6H), 0.90-0.84 (m, 3H).

Quelle