Triphenylphosphine → 3-(6-acetylamino-1,2,3,4-tetrahydro-naphthalen-1-yl)-3H-imidazole-4-carboxylic acid isopropyl ester

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Reaction Steps

To a suspension of N-(5-hydroxy-5,6,7,8-tetrahydro-naphthalen-2-yl)-acetamide (0.553 g, 2.69 mmol) and isopropyl 4-imidazolecarboxylate (0.290 g, 1.88 mmol), which can be prepared as described in Example 1, in THF (10 mL) at 0° C. is added triphenylphosphine (1.415 g, 5.39 mmol) and dimethyl azodicarboxylate (40% wt. in toluene, 1.97 g, 5.39 mmol). The cooling bath is removed and the mixture is stirred for 15 min. Water is added and the mixture is extracted with ethyl acetate. The organic phase is dried over sodium sulfate, filtered and concentrated. The resulting residue is purified by silica gel chromatography (elution with dichloromethane-methanol mixtures) to give 3-(6-acetylamino-1,2,3,4-tetrahydro-naphthalen-1-yl)-3H-imidazole-4-carboxylic acid isopropyl ester; MS: (ESI) m/z 342.2 (M+H)+; 1H NMR (400 MHz, MeOD) δ ppm 1.39 (d, J=6.3 Hz, 3 H), 1.40 (d, J=6.0 Hz, 3 H), 1.71-1.82 (m, 1 H), 1.83-1.92 (m, 1 H), 2.16 (s, 3H), 2.17-2.30 (m, 2 H), 2.86 (ddd, J=16.9, 8.3; 5.6 Hz, 1 H), 3.00 (dt, J=16.9, 5.6 Hz, 1 H), 5.25 (sept., J=6.3 Hz, 1 H), 6.30 (t, J=5.3 Hz, 1 H), 6.93 (d, J=8.3 Hz, 1 H), 7.34-7.36 (m, 2 H), 7.53 (d, J=1.8 Hz, 1 H), 7.74 (d, J=1.0 Hz, 1 H).

Provenance & Evidence