Triphenylphosphine → (R)-1-[4-(4-fluoro-benzyloxy)-phenyl]-5-oxo-pyrrolidine-3-carboxylic acid methyl ester

Beteiligte Stoffe

Reaktionsschritte

A solution of 4.3 mmol of 4-fluoro-benzylalcohol and 4.7 mmol of triphenylphosphine in 7 ml of tetrahydrofuran was added dropwise at 0° C. to a solution of 4.7 mmol of (R)-1-(4-hydroxyphenyl)-5-oxo-pyrrolidine-3-carboxylic acid methyl ester [Example 2 a) or 8 a)] and 4.7 mmol of diisopropyl azodicarboxylate in 11 ml of tetrahydrofuran. The mixture was left to warm to RT and stirring was continued for 18 hours. After addition of 2 g of silica gel, the reaction mixture was evaporated under reduced pressure. The material obtained was chromatographed on silica gel using first a 2:1-mixture, then a 1:1-mixture of heptane and ethyl acetate as the eluent, yielding (R)-1-[4-(4-fluoro-benzyloxy)-phenyl]-5-oxo-pyrrolidine-3-carboxylic acid methyl ester as a white solid; MS: m/e=344 (M+H)+.

Herkunft & Nachweise