Water → 2-(1-Boc-piperidin-4-ylmethylidene)amino-N-(5-chloropyridin-2-yl)-5-fluorobenzamide

Participants

Reaction Steps

A solution containing 1-Boc-piperidine-4-carboxaldehyde (3.0 g, ca. 14 mmol), 2-amino-N-(5-chloropyridin-2-yl)-5-fluorobenzamide (3.7 g, 14 mmol), and pyridinium p-toluenesulfonate (0.3 g, 1.4 mmol) in benzene (250 mL) was heated at reflux for 24 h with azeotropic removal of water. The solution was allowed to cool to room temperature; then the solvent was removed in vacuo and the residue was partitioned between ethyl acetate (300 mL) and water (150 mL). The organic phase was separated and washed again with water (150 mL) and then brine (150 mL); then dried with MgSO4, filtered and concentrated in vacuo to give 6.0 g (93%) of the title compound as an orange foam which was used directly in the next step without further purification.

Provenance & Evidence