A new reagent for the determination of the optical purity of primary, secondary, and tertiary chiral alcohols and of thiols
作者:Alexandre Alexakis、Stephane Mutti、Pierre Mangeney
DOI:10.1021/jo00030a034
日期:1992.2
A new reagent is described for the determination of the enantiomeric excess of chiral alcohols. This derivatizing agent (22) is a diazaphospholidine, easily prepared from hexamethylphosphorous triamide (HMPT) and a chiral diamine having a C2 axis of symmetry: (R,R)-N,N'-dimethylcyclohexane-1,2-diamine. A large array of primary, secondary, and tertiary alcohols, functionalized or not, as well as thiols were successfully tested. The derivatization is fast at room temperature, proceeds without kinetic discrimination, does not need any added cosolvent or coreagent, and may be run directly in an NMR tube. This new reagent allows an accurate analysis by P-31 NMR spectroscopy, and after conversion of the trivalent phosphorus derivative to the corresponding P-sulfide in the NMR tube, a new P-31 NMR spectrum may be recorded. In addition, most of the P-sulfide derivatives when submitted to GC or HPLC analyses exhibit base line separation.