1-ethynyl-4-fluoronaphthalene synthesis

Yield:904694-35-5 67.5%

Reaction Conditions:

with sodium hydroxide in toluene at 120; for 0.5 h;

Steps:

21.2

Dimethylhydroxymethyl-4-fluoro-1-naphthylacetylene (1.88 g, 8.23 mmol) and NaOH (396 mg, KISHIDA CHEMICAL CO., Ltd., 0.7 mm granular, 98% article, 9.90 mmol) were placed in a 30 mL two-neck flask equipped with a reflux condenser and the air inside the flask was replaced with Ar. 20 mL of toluene was added thereto and the mixture was refluxed at 120°C for 30 minutes. Diethyl ether was added to the reaction mixture and the mixture was washed with a saturated aqueous ammonium chloride solution and dried over magnesium sulfate. The solvent was distilled off under reduced pressure by an evaporator. The crude reaction product was purified by column chromatography (Hexane/AcOEt=100/0->1/10) using silica gel to give 946 mg of the desired compound as a yellow solid (yield: 67.5%). ¹H-NMR (300 MHz, CDCl₃) δ: 8.37-8.33 (m, 1H), 8.14-8.11 (m, 1H), 7.70-7.56 (m, 3H), 7.13-7.10 (m, 1H), 3.43 (s, 1H) [MS] EI (m/z): 170 (M⁺), CI (m/z): 171 (MH⁺)

References:

EP1847545,2007,A1 Location in patent:Page/Page column 43