Pyridine → HCID 131734643, compound

Participants

Reaction Steps

A 3 mL glass vial was equipped with a rubber septum and magnetic stir bar. The vial was brought into a glove box and charged with trimethyloxonium tetrafluoroborate (198 mg, 1.33 mmol). The vial was sealed and removed from the glove box. A separate 3 mL vial was charged with 2-methoxy-6-pyridinecarboxaldehyde (Aldrich #662933, 184 mg, 1.34 mmol) and was dissolved in CH2Cl2 (1.5 mL). The solution of pyridine was added via syringe onto the solid trimethoxonium tetrafluoroborate at room temperature. The vial which contained the pyridine was rinsed with CH2Cl2 (1 mL) and the rinse solution was injected into the reaction vial. The reaction vial was kept at room temperature and stirring was maintained at ca. 400-600 rpm. Over the course of the reaction (17 h), the solid trimethoxonium tetrafluoroborate gradually dissolved, the solution clarified, and an oil gradually formed. At the end of the reaction, hexanes (2 mL) were added after which stirring was stopped. Any solid or oil was allowed to settle and the solvent was removed by glass pipette. The solid or oil was then rinsed with several portions of hexanes followed by diethyl ether. Residual solvent was then removed in vacuo to provide the compound N-methyl-6-methoxy-2-pyridinecarboxaldehyde tetrafluoroborate. This oil was used for oxime formation without further purification.

Provenance & Evidence