Yield:5003-48-5 63%

Reaction Conditions:

with di-tert-butyl-diazodicarboxylate;triphenylphosphine in dichloromethane for 8.5 h;Cooling with ice;Solvent;Reagent/catalyst;

Steps:

1-3 Example 1
Under ice water bath conditions,In a 50mL flask,First add 0.3023g acetaminophen and 0.6295g triphenylphosphine,Then add 20mL of dichloromethane,Then add 0.552g of di-tert-butyl azodicarboxylate,Finally, 0.4324g of acetylsalicylic acid was added in steps within 20min,After keeping the ice water bath for 20 minutes,Return to normal temperature reaction,The reaction time is 8.5h,The yield is 63.0%;Crystallization and separation with 95% ethanol,After three recrystallizations,White benoate crystals are obtained,The total yield based on acetaminophen was 52.6%.The product quality conforms to the 2005 edition of "Chinese Pharmacopoeia".

References:

Guangxi University of Technology;Huang Xiaocheng;Zhang Baodong;Su Hui;Lin Hanbao CN111056968, 2020, A Location in patent:Paragraph 0021-0037

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