Trimethyl orthoformate → 4-bromo-N-methylpyridin-3-amine

Participants

Reaction Conditions

Reaction Steps

A mixture of 4-bromo-pyridin-3-ylamine (2 g, 11.56 mmol, CAS RN 239137-39-4) in trimethyl orthoformate (19 mL, 173.4 mmol, CAS RN 149-73-5) and a catalytic amount of TFA (1 drop) was heated to reflux for 2 hours. Volatiles were removed in vacuo, the resultant dark brown material was dissolved in THF (40 mL), treated portionwise with LiAlH4 (440 mg, 11.56 mmol) at 0° C. and then left stirring at 0° C. for 30 minutes. The reaction mixture was quenched with saturated aqueous NH4Cl solution (15 mL), filtered through a bed of celite, and the residue further washed with EtOAc (30 mL). The combined organic layers were washed with brine, dried over anhydrous Na2SO4, filtered, and evaporated off in vacuo. The residue was purified by column chromatography over alumina (10% EtOAc in n-hexane) to afford the title compound. Light yellow oil (875 mg, 40%). MS (ESI): m/z=187.2 [M+H]+.

Provenance & Evidence