[(3S,4R)-1-benzyl-4-(4-chloro-phenyl)-pyrrolidin-3-yl]-carbamic acid methyl ester → rel-(3S,4R)-1-Benzyl-4-(4-chlorophenyl)-N-methylpyrrolidin-3-amine

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Reaction Conditions

Reaction Steps

To a suspension of [(3S,4R)-1-benzyl-4-(4-chloro-phenyl)-pyrrolidin-3-yl]-carbamic acid methyl ester (49.22 g, 142.7 mmol) in THF (520 mL) borane-tetrahydrofurane complex solution (1 M in tetrahydrofurane, 571 mL, 571 mmol) was added slowly over a period of 25 min. The reaction mixture was stirred for 19 h at 60° C. and then quenched with aqueous HCl (1N, 570 mL, dropwise over 60 min). The mixture was stirred for further 21 h at 60° C. After cooling to ambient temperature, tetrahydrofurane was distilled away and the residue was separated between tert-butylmethylether (1500 mL) and aqueous HCl (1N, 1000 mL). The aqueous layer was set to pH=10 with aqueous sodium carbonate (saturated, 2000 mL) and then extracted with tert-butylmethylether (twice 1500 mL). The organic layers were washed with brine (750 mL), combined and was dired over sodium sulfate. Concentration and filtration over silicagel (ethyl acetate:methanol, triethylamine=90:5:5) afforded the title compound (34.38, 80%) as a light yellow liquid. MS m/e: 301.4/303.4 [M+H]+.

Provenance & Evidence