title: A New Stereoselective Synthesis of Phosphiranes.
abstract: The synthesis of phosphiranes from primary phosphines and diol ditosylates was found to be stereoselective, and chiral phosphiranes were prepared from optically pure diols. The four optical isomers of 1-mesityl-2,3-dimethylphosphirane, (2S,3S)-(+)-3, (2R,3R)-(-)-4, anti-cis-(meso)-5, and syn-cis-(meso)-6, were all synthesized from mesitylphosphine and the corresponding diol ditosylates. Compound 6 was unstable, but compounds 3, 4, and 5 were all isolated in pure form. Their structure assignments were based on the NMR coupling constants J(P-H) and J(P-C). The phosphiranes were transformed into tungsten pentacarbonyl complexes. Tungsten tetracarbonyl-triphenylphosphine complexes (22, 23, 24) of compounds 3, 4, and 5 were synthesized in high yields by the reaction of the phosphiranes and W(CO)(4)(PPh(3))(THF). The absolute stereochemistry of the phosphiranes 3, 4, and 5 was determined by X-ray crystal structure analysis of compounds 22, 23, and 24. Stereochemical effects on NMR coupling constants and mass spectra of the phosphiranes are discussed.
authors.affiliation: Department of Chemistry, Washington University, St. Louis, Missouri 63130-4899.
authors.forename: Xinhua
authors.initials: X
authors.lastname: Li
authors.forename: Kerry D.
authors.initials: KD
authors.lastname: Robinson
authors.forename: Peter P.
authors.initials: PP
authors.lastname: Gaspar