Dedicated to the memory of Björn Roos (1937–2010), one of the fathers of modern multiconfigurational quantum chemistry, who also cared deeply about chemical applications, and a fun and inspiring friend to countless theoretically oriented chemists.

Acid-catalyzed condensation of pyrrole, 4-trifluoromethylbenzaldehyde, and azulene, followed by DDQ oxidation, has resulted in the isolation of the novel macrocycle azulicorrole, arguably the first example of a carbacorrole aside from N-confused corrole. Despite poor yields (<1%), the free ligand could be structurally characterized and converted to the formal Cu(III) and Au(III) derivatives, of which ...

Two-component relativistic time-dependent density functional theory calculations with spin-orbit coupling predict yellow and orange–red absorption for BiPh5 and BiMe5, respectively, providing an excellent explanation for their respective violet and blue–violet colors. According to the calculations, the visible absorption is clearly attributable to a single transition from a ligand-based HOMO ...

Copper undecaarylcorroles were found to undergo acid-induced demetalation with unusual ease under both reductive and nonreductive conditions. The resulting free-base undecaarylcorroles were found to be rather reactive, readily photooxygenating to yield 5/10-hydroxyisocorroles and open-chain tetrapyrroles. The use of nonreductive conditions led to 50-75% yields of undecaarylisocorroles, a new class ...

Presented herein is a first investigation of the chemical reactivity of osmium-nitrido corroles, which are known for their unusual thermal, chemical, and photochemical stability. Elemental chlorine perchlorinates the β-positions of the triarylcorrole but leaves the OsN unit untouched. The OsN unit is also unaffected by a variety of other electrophilic and nucleophilic reagents. Upon photolysis, ...

A porphyrin cis tautomer, where the two central NH protons are on adjacent pyrrole rings, has long been invoked as an intermediate in porphyrin tautomerism. Only recently, however, has such a species been isolated and structurally characterized. Thus, single-crystal X-ray structure determinations of two highly saddled free-base porphyrins, β-heptakis(trifluoromethyl)-meso-tetrakis(p-fluorophenyl)porphyrin, ...

Since the discovery of decamethylsilicocene over three decades ago, chemists have successfully isolated a variety of divalent silicon compounds by orchestrating steric and electronic effects to their advantage. Two broad strategies of electronic stabilization appear to have been widely deployed, namely, π-conjugation as in diaminosilylenes and π-complexation as in decamethylsilicocene and ...

Extensive DFT calculations with several exchange–correlation functionals indicate that molybdenum-dichlorido Viking helmet corroles are noninnocent with significant Mo^IV-corrole^˙2− character. The effect is mediated by a Mo(4d)-corrole(π) orbital interaction similar to that postulated for MnCl, FeCl and FeNO corroles. The effect also appears to operate in tungsten-dichlorido ...

The influence of fluorinated substituents on the luminescent properties of rhenium-oxo, osmium-nitrido, and gold triarylcorroles was studied via a comparison of four ligands: triphenylcorrole (TPC), tris(ptrifluoromethylphenyl)corrole (TpCF₃PC), tris{3,5-bis(trifluoromethyl)- phenyl}corrole (T3,5-CF₃PC), and tris(pentafluorophenyl)corrole (TPFPC). For each metal series ...

Six-coordinate iridium(III) triarylcorrole derivatives, Ir[T<i>p</i>XPC)]L₂, where T<i>p</i>XPC = tris(para-X-phenyl)corrole (X = CF₃, H, Me, and OCH₃) and L = pyridine (py), trimethylamine (tma), isoquinoline (isoq), 4-dimethylaminopyridine (dmap), and 4-picolinic acid (4pa), have been examined, with a view to identifying axial ligands most conducive to near-infrared ...