1,1'-Carbonyldiimidazole → HCID 131730374, compound

Participants

Reaction Steps

The compounds were prepared as described in Example 1, Step 1 starting from crude 1-(methoxycarbonyl)-2-(2-methyl-2-phenylpropyl)piperidine-4-carboxylic acid (7.24 g, 22.7 mmol) (Reference compound 7), magnesium chloride (2.16 g, 22.7 mmol) and ethyl potassium malonate (5.79 g, 34 mmol) and subsequently carbonyldiimidazole (4.41 g, 27.2 mmol) which gave trans-methyl 4-(3-ethoxy-3-oxopropanoyl)-2-(2-methyl-2-phenylpropyl)piperidine-1-carboxylate (1.59 g, 18%) and cis-methyl 4-(3-ethoxy-3-oxopropanoyl)-2-(2-methyl-2-phenylpropyl)piperidine-1-carboxylate (2.38 g, 27%). Trans isomer: 1H NMR (600 MHz, cdcl3) δ 1.20-1.50 (m, 10H), 1.59-1.84 (m, 2H), 1.90 (m, 2H), 2.50-2.89 (m, 2H), 3.16 (m, 2H), 3.58 (m, 4H), 4.17 (m, 4H), 7.06-7.51 (m, 5H). Cis isomer: 1H NMR (600 MHz, cdcl3) δ 1.20-1.41 (m, 10H), 1.57-1.74 (m, 3H), 1.79 (d, 1H), 2.03 (m, 1H), 2.53 (m, 1H), 2.83-3.02 (m, 1H), 3.40 (m, 2H), 3.48-3.68 (m, 4H), 4.03 (m, 1H), 4.12-4.22 (m, 2H), 7.18-7.44 (m, 5H).

Provenance & Evidence