Toluene → Atorvastatin tert-butyl ester

Participants

Reaction Steps

An argon inerted reactor was charged with 7-[2-(4-fluorophenyl)-5-isopropyl-3-phenyl-4-phenylcarbamoyl-pyrrol-1-yl]-3,5-dioxo-heptanoic acid, t-butyl ester (V-A, 100.0 mmol, prepared as indicated in U.S. Pat. No. 6,476,235) and toluene (245 ml). To the reaction mixture was added triethyl amine (55 ml), followed by slow addition of formic acid (7.5 ml). The vessel and its contents was degassed via three vacuum/argon purges. Under a steady flow of argon, the complex of Ruthenium, [N-[(1R,2R)-2-(amino-κN)-1,2-diphenylethyl]-4-methylbenzenesulfonamidato-κN]chloro[(1,2,3,4,5,6-η)-1,3,5-trimethylbenzene]-(1.25 g) was added, and the vessel and its contents were degassed via one vacuum/argon purge. The reaction mixture was stirred for 24 hours and condensed to a foamy solid. The crude (3R,5R)-7-[2-(4-fluorophenyl)-5-isopropyl-3-phenyl-4-phenylcarbamoyl-pyrrol-1-yl]-3,5-dihydroxy-heptanoic acid, t-butyl ester may be carried on through subsequent steps without purification, or optionally, can be isolated via flash column chromatography on silica gel, eluting with ethyl acetate-heptane mixtures. HPLC analysis (YMC ODS AQ S5; 1 ml/min; 30° C.; 254 nm: CH3CN/H2O w/0.1% formic acid, 60:40 (0–5 min) to 100:0 (15–22 min) to 60:40 (25 min) indicated a syn:anti ratio of 6:1 tr(syn)=13.9 min tr(anti)=13.5 min

Provenance & Evidence