2-Bromopropane → 1-Isopropylpyridinium-4-carboxamide bromide

Participants

Reaction Steps

A solution of 200 mL of DMF, containing 50.0 g of isonicotinamide and 60 mL of 2-bromopropane, was refluxed 5.75 h. A white insoluble solid filtered from this cool solution gave 64.9 g (65%) of 1-isopropylpyridinium-4-carboxamide bromide, m/e=165, NMR. Catalytic reduction of this salt, with PtO2 in MeOH, gave 65.2 g (98%) of 1-isopropylpiperidine-4-carboxamide hydrobromide, m/e=171. An aqueous solution of this salt was basified, evaporated to dryness, and extracted with EtOAc to give 39.7 g (90%) of 1-isopropylpiperidine-4-carboxamide free base.

Provenance & Evidence