Triethylamine → 1-{[4-({[(3-isopropyl-2-oxo-2,3-dihydro-1H-benzimidazol-1-yl)carbonyl]amino}methyl)piperidin-1-yl]methyl}cyclopentanecarboxylic acid

Beteiligte Stoffe

Reaktionsschritte

A mixture of 1-isopropyl-1,3-dihydro-2H-benzimidazol-2-one (10 g, 56.8 mmol) and chloroformic acid 4-nitrophenyl ester (11.4 g, 56.8 mmol) in CH2Cl2 (150 mL) was stirred at room temperature for 5 min. To this mixture, Et3N (17.4 mL, 125 mmol) was added slowly and the resulting mixture was added to a mixture of 1-{[4-(aminomethyl)piperidin-1-yl]methyl}cyclopentanecarboxylic acid 4-methylbenzene sulfonate (23.4 g, 56.8 mmol, Step 8) in CH2Cl2 (75 mL) at room temperature. After stirring for 10 min, Et3N (7.9 mL, 56.8 mmol) was added and the resulting mixture was stirred at room temperature for 2 hr. This mixture was washed with 1 N HCl aq (100 mL). Organic layer was concentrated at 50° C. until ca 5 vol and it was replaced by acetone (50 mL×3) at 80° C. until ca 5 vol. To this mixture, H2O (100 mL) was added at 80° C. and the resulting mixture was concentrated at 100° C. After cooling down to 50° C., 20% N,N-dimethylaminoethanol aqueous solution (100 mL) was added to this mixture and the solid was observed. The resulting mixture was cooled in ice cold bath and it was stirred for 18 hrs at that temperature. This mixture was filtered and the obtained solid was washed with H2O (100 mL), dried at 50° C. under vacuum to afford 17.9 g (71%) of the titled compound as white solid.

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