Dimethyl cyclopentane-1,3-dicarboxylate (cas# 2435-36-1) is a useful research chemical, It can be used as organic synthesis intermediate and pharmaceutical intermediate, mainly used in laboratory research and development process and chemical production process.
A 5-L, 3-neck, roundbottom flask was equipped with a mechanical stirrer, a J-KEM temperature controller, and a reflux condenser. The flask was charged with cyclopentane-l,3-dicarboxylic acid(357 g, 2.262 mol) and methanol (1.75 L). The solution was cooled to 7 °C using anice/water bath. Concentrated sulfuric acid (70 mL) was added dropwise over 30 minresulting in an exotherm up to 12 °C. The reaction mixture was heated to reflux andstirred for 16 h when TLC analysis (10 percent methanol/ethyl acetate) indicated that thereaction was complete. The reaction mixture was concentrated, redissolved in methyl- 179 -ATI-2514175vl tert-butyl ether, and washed with saturated aqueous sodium bicarbonate (2 x 150 mL) and brine (2 x 150 mL). The organic layer was dried over sodium sulfate, filtered, and concentrated. The resulting clear oil was dissolved in hexane (2 L) and treated with a 2 N aqueous sodium hydroxide solution (950 mL) until the pH ~ 10. The layers were separated and the aqueous layer was extracted with hexane (4 x 1 L). The organic layers were combined, dried over sodium sulfate, filtered, and concentrated to provide 360 g (100percent) of dimethyl cyclopentane-l,3-dicarboxylate as a clear oil.
[1] Patent: WO2012/145569, 2012, A1. Location in patent: Page/Page column 179; 180
[2] Journal of Medicinal Chemistry, 2011, vol. 54, # 10, p. 3480 - 3491
[3] Patent: US2018/170931, 2018, A1. Location in patent: Paragraph 0188
[4] Patent: WO2018/112382, 2018, A1. Location in patent: Page/Page column 174
[5] Tetrahedron Letters, 2005, vol. 46, # 18, p. 3201 - 3203
