Chiral separation ofS-(+)- andR-(−)-ibuprofen by thin-layer chromatography. An improved analytical procedure

Abstract

Chiral separations by gas and liquid chromatography (thin-layer chromatography included) remain an analytical challenge, hence even moderate success in this field is very likely to be regarded as a valuable separation achievement. There has been only one literature report of chiral separation of S -(+)- and R -(−)-ibuprofen by TLC. The original procedure was performed with laboratory-coated glass plates and resolution of the two enantiomers in one-dimensional mode was incomplete. In an attempt to enhance the resolution the authors made use of less convenient and considerably more time-consuming two-dimensional TLC and the final result was not very impressive (Δ R F = 0.03). These chromatograms were visualized by exposure of the developed plates to iodine vapor and no direct confirmation of the identity of the two chromatographic bands was produced.The goals of this study were: (i) to adapt the experimental conditions used for this separation to commercial chromatographic glass plates; (ii) to enhance the ...