Novel Aspects of Phosphorus Analogues of Arduengo Carbenes: from Very Stable Phosphenium Ions to Umpolung of P-H Bonds
摘要:
According to the results of structural and computational studies, P-halogeno-diazaphospholenes are not ionic but feature weak and polar covalent P-X bonds. Similar bond weakening effects which are attributable to l.p. (N)-sigma*(P-X) hyperconjugation were also established for P-H substituted diazaphospholenes. The physical properties of these compounds suggest a hydridic nature of the P-H bond. and their reactivities display an "Umpolung" as compared to known reaction patterns of phosphines.