(E)-5-(4-(2-(5-ethylpyridin-2-yl)ethoxy)benzylidene)thiazolidine-2,4-dione → Pioglitazone, (R)-

Participants

Reaction Steps

A stock solution of the Rh(COD)2BF4 (10.6 mg, 26.1 μmol) in DCM (9.5 mL) was made in a glove box. Ligand SL-WO03-2 ((S)-1-[(S)-2-(2i -diphenylphosphinophenyl)ferrocenyl]ethyl-dicyclohexyl phosphine) (8.4 mg, 12.5 μmol), was weighed into a vial and 500 μL of the Rh(COD)2BF4 stock solution was added. A solution of 5-[1-{4-[2-(5-ethyl-pyridin-2-yl)-ethoxy]-phenyl}-meth-(E)-ylidene]-thiazolidine-2,4-dione (4.5 mL of a stock solution containing 78.2 mg in 35 mL MeOH) was added to the reaction vial containing the catalyst solution. The vial was purged with N2 (5×) and H2 (5×) and finally charged with 25 bar of H2. After 18 h the H2 was released and the reaction vial was purged with N2 (3×). A sample of the reaction vial was taken and diluted with an equal volume of EtOH containing 1% formic acid. e.e. (Method 4) 75%, Rt 36.11 min, conversion 50%.

Provenance & Evidence