4-Pentynoic acid → 5-(But-3-ynyl)-3-o-tolyl-1,2,4-oxadiazole

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

In a reactor tube, a mixture of N′-hydroxy-2-methylbenzamidine (555 mg, 3.7 mmol), 4-pentynoic acid (363 mg, 3.7 mmol), HOBT (0.56 g, 3.7 mmol) and EDCI.HCl (1.06 g, 5.55 mmol) in dioxane (7.4 mL) was stirred at R.T for 3h. After this time the mixture was heated at 80° C. overnight in a reaction block. The mixture was concentrated. The organic layer was washed with water, NaOH 1N and water. The solvent was evaporated in a Genevac for 75 min at 40° C. using the low boiling point program. The crude product was purified by flash chromatography (Prepacked 10 g silicagel column) with DCM as eluent to afford 250 mg of 5-(but-3-ynyl)-3-o-tolyl-1,2,4-oxadiazole (Yield: 32%) as yellow oil.

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