Potassium Phosphate, Tribasic → 4-[[6-Chloro-5-[(cyclohexylacetyl)amino]-2-quinolinyl]methyl]-1-piperidinecarboxylic acid, 1,1-dimethylethyl ester

Beteiligte Stoffe

Reaktionsschritte

9-Borabicyclo[3.3.1]nonane dimer solution (3.5 mL, 2M in tetrahydrofuran) was added to 4-methylene-1-piperidinecarboxylic acid, 1,1-dimethylethyl ester (prepared according to the method of Journal of Medicinal Chemistry 2002, 45, 3143) (345 mg) at room temperature under nitrogen. The mixture was refluxed for 3 hours after which it was cooled to room temperature. Potassium phosphate (1 g) in water (1 mL) was added and the mixture stirred for 30 minutes. N-(2,6-Dichloro-5-quinolinyl)-cyclohexaneacetamide (Example 1 (a)) (300 mg) in N,N-dimethylformamide (2 mL) was added followed by tetrakis(triphenylphosphine)palladium(0) (20 mg). The reaction mixture was heated to 80-90° C. for 4 hours under nitrogen. On cooling to room temperature the reaction mixture was filtered through diatomaceous earth and the tetrahydrofuran removed under vacuum. The resulting mixture was poured into water and extracted with ethyl acetate. The combined organic extracts were dried, filtered and evaporated. Purification (SiO2, ethyl acetate:isohexane 20:80 as eluant) gave the sub-titled compound (200 mg).

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