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ChemicalBook CAS DataBase List Ethyl 2-(triphenylphosphoranylidene)propionate
5717-37-3

Ethyl 2-(triphenylphosphoranylidene)propionate synthesis

6synthesis methods
Ethyl 2-(triphenylphosphoranylidene)propionate was prepared this reagent from ethyl 2-bromopropanoate and triphenylphosphine.A 500-mL, one-necked, round-bottomed flask equipped with an egg-shaped magnetic stirring bar is charged with triphenylphosphine (52.46 g, 200.0 mmol), ethyl acetate (130 mL), and ethyl 2-bromopropanoate (26.03 mL, 200.0 mmol). A reflux condenser is attached to the flask and the solution is heated under reflux (oil bath temperature: 75-80 °C) under argon for 24 h. The resulting white precipitate is collected through suction filtration on a Büchner funnel and washed with ethyl acetate (100 mL). The salt is dissolved in dichloromethane (500 mL) and the solution is transferred to a 1-L separation funnel. Aqueous sodium hydroxide solution (2 M, 200 mL) is added and, after vigorously shaking, the organic and aqueous layers are separated. The aqueous phase is extracted with dichloromethane (100 mL). The combined organic phases are washed with brine, dried over anhydrous Na2SO4, filtered, and concentrated at 30 °C under rotary evaporation (20-25 mmHg); drying under vacuum (0.1-0.2 mmHg) affords 54.51 g (75.2%) of ethyl 2-(triphenylphosphoranylidene)propionate as a light-yellow solid, mp 156-158 °C.
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Yield:5717-37-3 96%

Reaction Conditions:

in toluene at 80; for 12 h;Green chemistry;Solvent;Temperature;Reagent/catalyst;

Steps:

2 Preparation of (carbethoxyethylidene)triphenylphosphorane

To 1000mL three-necked flask was added 131g of triphenylphosphine and 100g 2- bromopropionate, was added 200mL of toluene and then 500ml water, 80 ° C the reaction was stirred 12h. After completion of the reaction was cooled to 50 ° C, the aqueous layer was separated, washed with 50ml of toluene, cooled to room temperature, a solution of 10% potassium hydroxide solution was adjusted ΡΗ = 8.0-8.5, stirring was continued for lh. Filtered and the resulting cake was dried at 50 ° C, to give (carbethoxyethylidene)triphenylphosphorane 175 g of solid, yield 96%

References:

CN103910759,2016,B Location in patent:Paragraph 0026; 0027; 0034

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