Manipulating Aromaticity

The Nov. 14, 2011, Science & Technology Concentrates carried a delightful article entitled “Switching Off Aromaticity,” which draws attention to a laser technique that beautifully provides a possible way of exciting all unfunctionalized carbocyclic aromatic molecules into their possible nonaromatic energy states (page 35).

This work now complements our findings, below, that in some heteroaromatics, tropone, and cyclopropanone, aromaticity can be “switched on” or greatly augmented by their bonding to Lewis acids (and, of course, protons): “The Roles of Aromaticity in the Structure of DNA and Its Intercalation Complexes with Quinones,” J. Mol. Model., 10.1007/s008940100048 ; “Stereo-electronic Effects in Polynucleotides and Their Double Helices,” J. Mol. Struct., DOI: 10.1016/j.molstruc.2003.10.019; and “Using Molecular Modeling To Understand Some of the More Subtle Aspects of Aromaticity and Antiaromaticity,” J. Chem. Educ., DOI: 10.1021/ed100408s.

Nature has been manipulating aromaticity to its advantage for many years.

By Vernon G. S. Box
New York City