Tetrahydro-1H-pyrrolizine-7a(5H)-acetic acid ethyl ester synthesis

Yield:88069-56-1 49.6%

Reaction Conditions:

at 80 - 145; for 14 h;Temperature;

Steps:

12-14 Preparation of 7α-bis-pyrrolidine-ethyl acetate (IX)

Add 50 g of monoethyl malonate, 37.02 g (0.28 mol) of N-(3-carboxypropyl)butyrolactam (III) to a 500 mL four-necked flask equipped with a mechanical stirring and a thermometer, and raise the temperature to 140-145 ° C. , stirring for 2 hours, cooling to 80-85 ° C, adding 51.5 g (0.33 mol) of human malonate monoethyl ester potassium salt in 300 ml of monomethyl malonate solution, stirring for 12 hours, cooling to room temperature, Add to 500 ml of water, adjust to pH = 10-11 with sodium hydroxide, extract with dichloromethane (100 ml × 3), combine the organic phases, and dry and concentrate to give a colorless liquid 7α-bis-pyrrolidine-ethyl acetate ( IX) 16.2 g, yield 49.6%. .

References:

CN109867679,2019,A Location in patent:Paragraph 0078-0087