4-Chlorophenol → HCID 59166750, compound

Participants

Reaction Steps

(2S,4R)-4-Hydroxy-pyrrolidine-1,2-dicarboxylic acid 1-tert-butyl ester 2-methyl ester (CAS Reg. No. 74844-91-0) (1.10 g, 4.08 mmol) was dissolved in THF (25 ml) and 4-chlorophenol (0.78 g, 6.12 mmol) and triphenylphosphine (1.6 g, 6.12 mmol) were added. The solution was cooled in and ice bath and DIAD (0.96 ml, 4.88 mmol) added dropwise. The reaction was stirred at room temperature overnight. After evaporation of the solvent, the residue was dissolved in diethylether (20 ml) and pentane added until solution was only just maintained. The solution was seeded with triphenylphosphine oxide and cooled in ice. The resultant precipitate was filtered and the filtrate evaporated. The residue was purified by flash chromatography on silica (100 g), loading with pentane:diethylether (2:1 by volume) and eluting with pentane : diethylether (1: 1 by volume) to give the title compound as a colourless oil (1.35 g, 69%) containing a small impurity of diisopropylbicarbamate (CAS Reg. No.19740-72-8) by NMR.

Provenance & Evidence