Silacyclopropenium cation

A natural extension of the above studies is to charged aromatic molecules containing silicon. The potential for aromaticity in the silacyclopentadienyl anion 101 and the silacyclopropenium cation 102, both formally possessing an aromatic (4n + 2) -electron network, was studied by Gordon and coworkers2463. 101 is isoelectronic with the cyclopentadienyl anion and 102 with the cyclopropenium cation, both well established aromatic systems with high delocalization energies. 

FIGURE 43. Optimized structures (6-31G ) of the C2v and Cs silacyclopentadienyl anion (101)259 and of the silacyclopropenium cation (102)246a. Bond lengths are in A, bond angles in deg. Reprinted with permission from J. Org. Chem.y 51,5028 (1986). Copyright (1986) American Chemical Society259. 

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