Tris(chalcogenato)carbenium Ions [C(XR)3]+ (X O, S, Se, Te): An Experimental and Quantum-Chemical Comparison (pages 300–303)
Dietmar Ohlmann, Christina M. Marchand, Prof. Dr. Hansjörg Grützmacher, Grace Shiahuy Chen, David Farmer, Prof. Dr. Rainer Glaser, Antonio Currao, Prof. Dr. Reinhard Nesper and Dr. Hans Pritzkow
Article first published online: 22 DEC 2003 | DOI: 10.1002/anie.199603001
[C(OR)3]+ ions are stabilized differently than [C(XR)3]+ ions (X = S, Se, Te). While the stability of the RO-substituted carbenium ions can be attributed to the high polarity of the Cδ+ -Oδ− bond, the polarity of the C-X bond in the homologous S-, Se-, and Te-containing ions is reversed, and the stabilization is achieved by the σ-and π-dative effect of the chalcogen centers. These results were obtained by ab initio calculations on [C(XH)3]+ ions and by experimental studies on the new compounds [C(XR)3][PF6] (X = S, Se, Te; R = 2,4,6-iPr3C6H2).