Diisopropylethylamine → HCID 136170273, compound

Participants

Reaction Steps

To a solution of 5,6-diethyl-nicotinic acid hydrochloride (920 mg, 4.3 mmol) and Hünig's base (2.76 g, 21 mmol) in DCM (50 mL) is added TBTU (1.785 g, 5.55 mmol) and the mixture is stirred at rt for 5 min. 3-Ethyl-4,N-dihydroxy-5-methyl-benzamidine (1.14 g, 4.7 mmol) is added and the mixture stirred for 0.5 h. The mixture is diluted with DCM, washed with sat. aq. NaHCO3 solution, dried over MgSO4, filtered and concentrated. The crude 5,6-diethyl-nicotinic acid (3-ethyl-4,N-dihydroxy-5-methyl-benzamidine) ester (LC-MS: tR=0.79 min) is dissolved in dioxane (50 mL) and heated to 100° C. for 18 h. The solvent is evaporated and the crude product is purified by FC on silica gel eluting with heptane:EA 10:1 to give 4-[5-(5,6-diethyl-pyridin-3-yl)-[1,2,4]oxadiazol-3-yl]-2-ethyl-6-methyl-phenol (0.42 g) as a solid; LC-MS: tR=1.03 min, [M+1]+=338.09.

Provenance & Evidence