2-tert-Butyl-1,3-diisopropylisourea → Tert-butyl 4-(3-methylbutanoyl)benzoate

Participants

Reaction Steps

To a slurry of 4-(3-methylbutanoyl)benzoic acid (499 mg, 2.42 mmol) in dichloromethane (6 mL) was added O-tert-butyl-N,N′-diisopropylisourea (1.82 g, 9.07 mmol). The mixture was stirred at room temperature for 50 hours then diluted with tert-butyl methyl ether (75 mL). The mixture was washed with sat. aq sodium bicarbonate (50 mL), dried over anhydrous Na2SO4, and filtered, and the filtrate was concentrated. Purification by silica gel flash chromatography (ethyl acetate/heptane) gave tert-butyl 4-(3-methylbutanoyl)benzoate as a colorless oil. 1H NMR (400 MHz, CDCl3) δ 8.09-8.04 (m, 2 H), 8.00-7.94 (m, 2 H), 2.86 (d, J=6.8 Hz, 2 H), 2.37-2.23 (m, 1 H), 1.62 (s, 9 H), 1.01 (d, J=6.7 Hz, 6 H).

Provenance & Evidence