Stable Pentacoordinate Carbocations: Structure and Bonding

✍ Scribed by Israel Fernández; Einar Uggerud; Gernot Frenking

• Publisher: John Wiley and Sons
• Year: 2007
• Tongue: English
• Weight: 405 KB
• Volume: 13
• Category: Article
• ISSN: 0947-6539
• DOI: 10.1002/chem.200700744

✦ Synopsis

Abstract

We report that only elements more electropositive than carbon (Group 13, 14, and Be) form stable symmetrical H~n~ECH~3~EH~n~^+^ structures (E=Group 1, 2, 13, or 14 element) with a planar CH~3~ group symmetrically bonded to two EH~n~ moieties, in analogy with prototypical S~N~2 transition structures. Analysis of the bonding situation of these pentacoordinate carbon molecules was studied by means of an energy decomposition analysis (EDA) of the interaction energy. This shows that H~n~ECH~3~EH~n~^+^ molecules can be viewed as being composed of one CH~3~ group that is σ‐covalently bonded to two EH~n~ groups forming a three‐center, two‐electron bond.