Synthesis
Step 3d. Synthesis of 3-ethynyl-4-fluoroaniline (Compound 0605): Compound 0604 (1.49 g) obtained above was dissolved in 20 mL of methanol, 100 mg of potassium hydroxide was added and the reaction was stirred at room temperature overnight. Upon completion of the reaction, the reaction solution was concentrated, diluted to neutral with water and subsequently extracted with ether. The organic phases were combined, dried with anhydrous magnesium sulfate, filtered and concentrated to give 3-alkynyl-4-fluoroaniline 0605 (1.49 g, 85% yield) as a brown oil. The molecular weight of the product was 136 [M + 1]+ by LCMS. The obtained product can be directly used in the subsequent reaction without further purification.
References
[1] Patent: US2009/111772, 2009, A1. Location in patent: Page/Page column 77
[2] Patent: WO2008/33747, 2008, A2. Location in patent: Page/Page column 139
[3] Patent: US2009/76022, 2009, A1. Location in patent: Page/Page column 78
[4] Journal of Organic Chemistry, 1981, vol. 46, # 11, p. 2280 - 2286
[5] Patent: JP5680638, 2015, B2. Location in patent: Paragraph 0347-0348
