Methyl 1-benzyl-5-oxopyrrolidine-3-carboxylate → Methyl 1-benzylpyrrolidine-3-carboxylate

Beteiligte Stoffe

Reaktionsschritte

A solution of methyl 1-benzyl-2-oxo-4-pyrrolidylcarboxylate (D10, 35.4 g, 0.18 mole) in dry THF (135 ml) was added dropwise over 30 mins to 1M borane-THF solution (228 ml, 0.23 mole) at 0° C. under nitrogen, and when addition was complete the solution was heated under reflux for 1h. The solution was cooled to room temperature, then treated dropwise with 8% hydrogen chloride/methanol (114 ml, 0.25 mole HCl) and stirred for 18h, followed by 3h at reflux. The mixture was then concentrated in vacuo and the residue treated with water (40 ml), washed with ether (2×50 ml), basified with 40% sodium hydroxide solution, saturated with potassium carbonate and extracted with ether (3×70 ml). The combined extracts were dried (Na2SO4) and concentrated in vacuo to leave a yellow oil, which was purified by distillation (b.p. 146° C.0.7mm) to give the title compound (D11) as a colourless oil (19.8 g, 50%).

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