3-Pyridinecarboxaldehyde → 2-(Pyridin-3-ylmethylidene)-1-azabicyclo[2.2.2]octan-3-one

Participants

Reaction Steps

3-Quinuclidinone hydrochloride (8.25 kg, 51.0 mol) and methanol (49.5 L) were added to a 100 L glass reaction flask, under an nitrogen atmosphere, equipped with a mechanical stirrer, temperature probe, and condenser. Potassium hydroxide (5.55 kg, 99.0 mol) was added via a powder funnel over an approximately 30 min period, resulting in a rise in reaction temperature from 50° C. to 56° C. Over an approximately 2 h period, 3-pyridinecarboxaldehyde (4.80 kg, 44.9 mol) was added to the reaction mixture. The resulting mixture was stirred at 20° C.±5° C. for a minimum of 12 h, as the reaction was monitored by thin layer chromatography (TLC). Upon completion of the reaction, the reaction mixture was filtered through a sintered glass funnel and the filter cake was washed with methanol (74.2 L). The filtrate was concentrated, transferred to a reaction flask, and water (66.0 L) was added. The suspension was stirred for a minimum of 30 min, filtered, and the filter cake was washed with water (90.0 L) until the pH of the rinse was 7-9. The solid was dried under vacuum at 50° C.±5° C. for a minimum of 12 h to give 8.58 kg (89.3%) of 2-((3-pyridinyl)methylene)-1-azabicyclo[2.2.2]octan-3-one.

Provenance & Evidence