Sulfuric Acid → Tert-butyl Piperidine-4-carboxylate

Participants

Reaction Conditions

Reaction Steps

To isonipecotic acid (41.5 g; 320 mmol) was added 1,4-dioxane (200 mL). Thus, an inhomogeneous solution was obtained. Thereto was added 41.5 mL of concentrated sulfuric acid over 30 minutes. Into this inhomogeneous solution was bubbled 100 g of isobutene over 5 hours. After completion of the bubbling, the mixture was cooled to 0° C. and 750 mL of 2-N aqueous NaOH solution was added thereto. The resultant mixture was ascertained to be basic. Thereafter, a reaction product was extracted with 500 mL of diethyl ether, and the extract was dried with sodium sulfate and then concentrated to obtain 5.98 g of t-butyl isonipecotate as the target compound.

Provenance & Evidence