Ethyl Acetate → HCID 22952196, compound

Temperature

25 °C

A solution of the isomeric mixture of 3-cyclopentyl-2-(4-meth-anesulfonyl-phenyl)-acrylic acid ethyl ester [65.02 g, 0.202 mol, (E):(Z)=1.63:1] in methanol (504 mL) was treated with a 1N aqueous sodium hydroxide solution (423 mL, 0.423 mol). The reaction mixture was stirred at 25° C. for 20 h, at which time, thin layer chromatography indicated the presence of starting material. The reaction mixture was then concentrated in vacuo to remove some of the methanol (300 mL). The resulting reaction mixture was heated under reflux for 1 h, at which time, thin layer indicated the absence of starting material. The reaction mixture was then concentrated in vacuo to remove methanol. The remaining aqueous layer was acidified to pH=1 with concentrated hydrochloric acid and then extracted with ethyl acetate (2×1 L). The combined organic layers were dried over magnesium sulfate, filtered, and concentrated in vacuo to afford 3-cyclopentyl-2-(4-methanesulfonyl-phenyl)-acrylic acid (62.58 g) as a cream solid consisting of a 16.2:1 mixture of (E):(Z) isomers. The cream solid was treated with ethyl acetate (200 mL), and the resulting slurry was heated to a boil. The resulting white solid surrounded by a light yellow liquid of ethyl acetate was allowed to cool to 25° C. The solid was filtered to afford pure (E)-3-cyclopentyl-2-(4-methanesulfonyl-phenyl)-acrylic acid (41.18 g, 69%) as a white solid: mp 200-202° C.; EL-HRMS m/e calcd for C15H18O4S (M+) 294.0926, found 294.0921.

1. temperaturethe resulting slurry was heated to a boil
2. filtrationThe solid was filtered

ORD record

ord-22702d7ca20847f8973da791b88ee33b

Source dataset

uspto-grants-2002_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06353111B1