ABSTRACT
Transesterification of tris(hexafluoroisopropyl) phosphite with racemic 3-methyl-1-phenyl-butane-1,3-diol gave two isomeric hexafluoroisopropyl-substituted 1,2,3-dioxaphosphinanes. These cyclic phosphites were hydrolyzed rapidly and enantioselectively by water catalyzed by HCl. The respective metalated H-phosphonates were added to ethyl 3-chloropyruvate and underwent a stereospecific α-hydroxyphosphonate-phosphate rearrangement to protected phosphoenol pyruvates. This sequence with oxygen isotope-labeled enantiomers represents an alternative approach to P-chiral [16O,17O,18O]phosphoenol pyruvates.
Acknowledgements
The authors thank V. Philippitsch for performing the α-phosphonate-phosphate rearrangement with DBU as base, S. Felsinger for recording NMR spectra, E. Macoratti for the preparative HPLC separation, and J. Theiner for combustion analyses.