Toluene → HCID 22865001, compound

Participants

Reaction Conditions

Reaction Steps

Under an argon atmosphere, (1,5-cyclooctadiene)ruthenium(II) chloride polymer (10 mg, 3.6×10-2 mmol), (S)-(-)-bis(diphenylphosphino)-1,1'-binaphthyl (24 mg, 3.6×10-2 mmol), triethylamine (0.1 ml, 6.5×10-1 mmol) and toluene (5 ml) were stirred in a sealed tube at 140° C. for 6 h. The solvent was removed in vacuo from the obtained red solution. To the residue was added a tetrahydrofuran (5 ml)--ethanol (10 ml) solution of (2S,4R)-N-tert-butoxycarbonyl-4-tert-butyldimethylsiloxy-2-[2-(N-methylcarbamoyl)-1-oxoethyl]pyrrolidine (1.5 g, 3.9 mmol). The mixture was stirred under a hydrogen pressure of 4 kg/cm2 at 80° C. for 22 h. Then, the reaction solution was concentrated. The residue was subjected to silica gel column chromatography (Wakogel™ C-300, heptane-ethyl acetate=3:1→1:3) to give the title compound [1.19 g, yield: 79%; by high performance liquid column chromatography YMC PACKED COLUMN, AQ-32 S-5 120A ODS, developer:acetonitrile--water 70:30, detection at 210 nm (R)-isomer (polar compound):(S)-isomer (less polar compound)=1.89:1].

Provenance & Evidence