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 3 h. 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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