Abstract: The fusion of a small ring to benzene has been advocated as a way to induce bond alternation and reduce aromaticity. In this theoretical study (performed using the B3LYP/aug-cc-pVDZ method), we examine the effect of fusing 1 or 2 three-member rings to pyridine or phosphabenzene with comparison back to the parent system (benzene). The effect of the fusion on the aromaticity of the 6 member ring is analyzed in terms of resonance stablization energy, magnetic properties (NMR shifts and NICS), and geometric parameters.

Outline:

Introduction

Question and Method

Molecular Structures

Distances

Magnetic Properties

Resonance Stabilization Energy

Discussion

Conclusion