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ChemicalBook CAS DataBase List Fexofenadine
83799-24-0

Fexofenadine synthesis

8synthesis methods
-

Yield:83799-24-0 87%

Reaction Conditions:

Stage #1:4-[4-[4-(hydroxydiphenylmethyl)-1-piperidinyl]-1-oxobutyl]-α,α-dimethylbenzeneacetic acid with potassium hydroxide in methanol at 0 - 20; for 1 h;
Stage #2: with potassium borohydride in methanol at 50; for 3 h;Reagent/catalyst;

Steps:

1.6
(6) 40 g (0.08 mol) of 4-{4-[4-(hydroxybenzhydryl)-1-piperidinyl]-1-butyryl group was placed in a 500 ml three-necked flask equipped with a magnetic stirrer. }-α,α-dimethyl-phenylacetic acid (VI) and 150 ml of methanol,After cooling to 0 ° C, 80 ml of 1 N potassium hydroxide solution was added dropwise, and after the dropwise addition was completed,After adding 4.32 g (0.08 mol) of potassium borohydride and returning to room temperature for 1 hour, an additional 2.16 g of potassium borohydride was added, and the mixture was heated to 50 ° C for 3 hours.The pH was then adjusted to 5 with 50% phosphoric acid to precipitate a solid which was filtered and washed with water.The wet product is recrystallized and purified by using methanol and water mixed solvent to obtain 35 g of high-purity fexofenadine (I), the yield is 87%, and the HPLC content is >99.7%;

References:

Chizhou Dongsheng Pharmaceutical Co., Ltd.;Huang Xiao;Bu Gonggaofamingren CN104557671, 2018, B Location in patent:Paragraph 0047; 0053; 0064; 0065

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