Lithium Hydroxide → 3-(1,2,3,4-Tetrahydro-naphthalen-1-yl)-3H-imidazole-4-carboxylic acid

Beteiligte Stoffe

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Reaktionsschritte

To a solution of 3-(1,2,3,4-tetrahydro-naphthalen-1-yl)-3H-imidazole-4-carboxylic acid methyl ester, which can be prepared as described in Example 2, (0.510 g, 1.990 mmol) in ethanol (20 mL) is added aqueous 4M LiOH (5 mL, 20 mmol) causing an immediate precipitate to form. After 3 hours, the mixture is evaporated to dryness, re-dissolved in a minimum amount of water, and the pH is adjusted to 6 with aqueous 2M HCl, causing a precipitate to form. The reaction is cooled to 0° C. and allowed to stand for 30 minutes. The precipitate is then filtered off and washed with cold phosphate buffer (pH 6). Upon standing, a solid precipitates out of the phosphate buffer which is filtered and combined with the initial precipitate to yield, upon drying under high vacuum, 3-(1,2,3,4-tetrahydro-naphthalen-1-yl)-3H-imidazole-4-carboxylic acid; MS: (ESI) m/z 243.2 (M+H)+; 1H NMR (400 MHz, MeOD) δ ppm 1.77-1.96 (m, 2 H), 2.21-2.36 (m, 2 H), 2.87-2.95 (m, 1 H), 3.05 (dt, J=16.9, 5.8 Hz, 1 H), 6.57 (t, J=5.6 Hz, 1 H), 7.01 (d, J=7.8 Hz, 1 H), 7.18-7.26 (m, 1 H), 7.26-7.36 (m, 2 H), 7.55 (s, 1 H), 7.79 (d, J=1.0 Hz, 1 H).

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