Diisopropylethylamine → HCID 86717922, compound

Participants

Reaction Conditions

Reaction Steps

595 mg of 1-(azetidin-3-yl)pyrrolidine dihydrochloride (Example 219A, 2.75 mmol, purity about 92%, 1 equivalent) were reacted in 3 batches. To obtain the free base, the 1-(azetidin-3-yl)pyrrolidine dihydrochloride was passed over a StratoSpheres™ SPE column. To this end, the column was initially moistened with 1 ml of methanol. 1-(Azetidin-3-yl)pyrrolidine dihydrochloride, dissolved in 3 ml of methanol, was then passed over the column and the column was rinsed with 3 ml of methanol. The solution obtained was concentrated (the column retains about 0.9 mmol of salt). The free base was then initially charged in 26.8 ml of acetonitrile, 656 mg of 2-(Boc-amino)ethyl bromide (2.9 mmol, 1.05 equivalents) and 1.45 ml of N,N-diisopropylethylamine (8.25 mmol, 3 equivalents) were added and the mixture was stirred at 80° C. overnight. The reaction mixture was concentrated and purified by silica gel chromatography (mobile phase: cyclohexane/ethyl acetate 5:1; dichloromethane/methanol 10:1; dichloromethane/methanol 4:1 and dichloromethane/1 N ammonia in methanol 4:1). This gave 463 mg (67% of theory) of the title compound.

Provenance & Evidence