1,1'-((1R)-1-Methyl-1,2-ethanediyl)bis(diphenylphosphine) → (S)-1-[2-(tert-Butoxycarbonyl)-3-(2-methoxyethoxy)propyl]-1-cyclopentanecarboxylic acid

Beteiligte Stoffe

Reaktionsschritte

(E)-1-[2-(tert-Butoxycarbonyl)-3-(2-methoxyethoxy)prop-1-enyl]-1-cyclopentanecarboxylic acid cyclohexylamine salt (50 mg, 0.11 mmole), chloro(1,5-cyclooctadiene)rhodium(I)dimer (2.0 mg, 0.004 mmole) and (R)-(+)-1,2-bis(diphenylphosphino)propane (3.2 mg, 0.008 mmole) were charged to a glass vial and the top sealed with a rubber septum. The system was flushed with argon, methanol (0.5 mL) was added and the mixture hydrogenated in a steel bomb at 345 kPa (50 p.s.i.) and room temperature for 4 hours. The crude product was purified by chromatography on silica by eluting with diethyl ether/1% acetic acid to give, after combination and evaporation of appropriate fractions, the title compound as an oil, (22 mg, 61%) (ratio S:R 54.46), Rf =0.3 (ethyl acetate/hexane, 1:1+1% acetic acid).

Herkunft & Nachweise