Synthesis
3.3 Synthesis of methyl 1-aminocyclohexanecarboxylate hydrochloride
To a 20 mL methanol suspension containing 2 g (14 mmol) of 1-aminocyclohexanecarboxylic acid, hydrogen chloride gas was passed for 2 min. Subsequently, 1.2 mL (16.8 mmol) of thionyl chloride was slowly added to the resulting solution and the reaction mixture was heated to reflux for 6 hours. Upon completion of the reaction, the mixture was cooled to room temperature and subsequently concentrated under reduced pressure to remove the solvent. The concentrated residue was dissolved in 5 mL of methanol, and then 50 mL of ether was slowly added to this solution to induce precipitation of the product. Ultimately, 2.3 g of methyl 1-aminocyclohexanecarboxylate hydrochloride in white powder form was obtained in 85% yield.
References
[1] Indian Journal of Chemistry - Section B Organic and Medicinal Chemistry, 2006, vol. 45, # 8, p. 1942 - 1944
[2] Patent: US2011/9426, 2011, A1. Location in patent: Page/Page column 13
[3] Patent: WO2013/19091, 2013, A2. Location in patent: Paragraph 881-883
[4] Patent: US2014/206875, 2014, A1. Location in patent: Paragraph 0482-0484
[5] Journal of Medicinal Chemistry, 1984, vol. 27, # 12, p. 1663 - 1668
