Synthesis of 1,2-Biphospholide Ions

摘要

To date, the 1,2-diphospholide ions are the only members of the poiyphosphacycioperuadienide family that have not yet been synthesized. Their preparation would permit 'he completion of a series of aromatic species that results from the successive replacement of sp~2-CH units in an aromatic hydrocarbon by isolobal sp~2-P units. No such complete series exists for any heteroatom. Several literature reports suggest that, were they made. 1.2-diphosphoiide ions would be stable: Padma Malar has calculated similar arornaticity indexes for the hypothetical [1,2-C_3H_3P_2]~- and the known [1,2,3-C_2H_P_3]~- anion. Furthermore. two groups have described ferrocene derisativei containing eta~5-l,2-diphosphciyl ligands, and more recently a zwitterionic pliosphoiederivative has been reported.