Pro-aromatic molecules have higher-energy diradicaloid states that are significantly influenced by resonance structures in which conjugated rings take on Hückel-aromatic character. Recently, it has been argued there also pro-aromatic adopt central units with 4nπ-electron Baird-aromatic character the T1 state, although detailed analysis suggests these compounds better labelled as Hückel–Baird hy...

Electrophilic aromatic substitution (EAS) represents one of the most important classes of reactions in all of chemistry. One of the "iron laws" of EAS is that an electron-rich aromatic ring will react more rapidly than an electron-poor ring with suitable electrophiles. In this report, we present unique examples of electron-deficient arenes instead undergoing preferential substitution in intramo...

The N-arylindole subunit is an important species in many biologically active and pharmaceutically important compounds, which display antiestrogen [1], analgesic [2], antiallergy [3], antimicrobial [4], and neuroleptic activity [5]. Although the traditional coppercatalyzed coupling of an aryl halide with a heteroatombased nucleophile, the Ullmann-type coupling reaction, has remained a standard m...

The synthesis and conformational behavior of two cyclodextrin dimers containing aromatic bipyridine spacers is presented. The proton NMR spectra of these dimers in aqueous solution show a doubling of signals in the aromatic region due to complete or partial self-inclusion of the spacer. The degree and the strength of self-inclusion is dependent on the substitution pattern of the bipyridine unit...

An exhaustive and systematic study of the structural and electronic properties of cyclooctatetraene (COT) upon substitution of hydrogen atoms by fluoro and cyano groups has been carried out in order to analyse the influence of both substituents on the aromaticity. We found that C-C distances decrease with fluoro substitution while in cyano derivatives the opposite happens. All the compounds ret...

Iron containing porous organic polymers (Fe-POPs) have been synthesized by a facile one-pot bottom-up approach to porphyrin chemistry by an extended aromatic substitution reaction between pyrrole and aromatic dialdehydes in the presence of small amount of Fe(III). The Fe-POPs possess very high BET surface area, large micropores and showed excellent CO(2) capture (~19 wt%) at 273 K/1 bar.

A direct nitration of aromatic sulfonamides using sodium nitrite as the nitrating agent has been developed. The reaction shows typically mono-substitution selectivity and can be enlarged to the gram scale with good yield.

A new reaction of oxidative substitution of aromatic carboxyl groups on stable trityl radical derivatives (TAMs) by various nucleophiles is described; it leads to a wide variety of new persistent and diversely substituted TAM radicals.

The nitro group of methyl 3-nitropyridine-4-carboxylate (1) has successfully been replaced by fluoride anion via nucleophilic aromatic substitution to give the 3-fluoro- pyridine-4-carboxylate 2.