1-Benzyl-4-(4-chloro-3-fluoro-phenyl)-2,5-dihydro-1H-pyrrole-3-carboxylic acid → (3S,4S)-1-Benzyl-4-(4-chloro-3-fluoro-phenyl)-pyrrolidine-3-carboxylic acid

Participants

Reaction Steps

A 2-l Hastelloy C4 autoclave was charged under argon with 1-benzyl-4-(4-chloro-3-fluoro-phenyl)-2,5-dihydro-1H-pyrrole-3-carboxylic acid (30.0 g, 90.4 mmol), [Ru(OAc)2((R)-2-Furyl-MeOBIPHEP)] (275.5 mg, 0.36 mmol, S/C 250) and methanol (1.2 l). The asymmetric hydrogenation was run for 20 h at 30° C. under 40 bar of hydrogen (99.2% conversion). After the pressure was released, a sample of the white suspension was evaporated to dryness. Crude (S,S)-Id was obtained with 97.9% purity and >99.9% ee.

Provenance & Evidence