The structure of a thiadiazole-containing expanded heteroazaporphyrinoid determined by gas electron diffraction and density functional theory calculations

Abstract

The molecular structure of a macrocycle with a 24-membered ring, a thiadiazole-containing expanded heteroazaporphyrinoid, has been, for the first time, directly characterised by a synchronous gas electron diffraction and mass spectrometric experiment and DFT calculations; the molecule has the equilibrium structure of C(3h) symmetry with a planar macrocycle.

Thiadiazole-Сontaining Macrocycles as Core-Modified Analogues of Phthalocyanine

“…The gas-phase molecular structure of tert-butylsubstituted Mc has been studied by a synchronous gas electron diffraction and mass spectrometric experiment and density functional theory calculations using the B3LYP hybrid method and cc-pVTZ basis sets. [19,20] Now it is evident that this compound contains three 1,3,4-thiadiazole rings and three 5-tert-butylisoindole subunits connected to each other via azabridges, and is therefore, a macrocyclic system of the ABABAB-type. It is also interesting to note that the molecule has a structure with a planar macrocycle and the thiadiazole rings oriented in such a way that the sulfur atoms point outwards from the inner cavity.…”

Synthesis and Properties of AABAAB-Type Macroheterocyclic Compounds with Fragments of 1,2,4- and 1,3,4-Thiadiazole

“…A white residue was filtrated and dried. Yield: 0.57 g (59 % (3,7,11,15,19,23)hexaazacyclotetracosene (8). A mixture of 4 (0.16 g, 0.62 mmol) and 1 (0.05 g, 0.31 mmol) was dissolved in phenol at 100-110 o C and reacted for 50 hours.…”

“…[9,10] Their structures were confirmed by gas electron diffraction and X-ray crystallographic analysis. [11][12][13][14] The compounds exhibit an expanded cavity which is able to contain up to three transition metal atoms, [8,15,16] possess high thermal stability, [17] show interesting electrochemical and photophysical properties [14,18] and are of particular interest as objects of supramolecular chemistry.…”

Theoretical Study of Oxozirconium Porphyrin, Octamethylporphyrin, Porphyrazine and Phthalocyanine Complexes

“…Such level of theory has been found to yield accurate structural parameters in earlier combined (experimental and theoretical) studies of oxotitanium phthalocyanine [2] and other large macroheterocyclic molecules. [16][17][18][19][20] Singlet and triplet excited states and the electronic spectra were studied using time-dependent density functional theory (TDDFT) implemented in PC GAMESS 7.0. [9] In all four molecules the molecular orbitals formed mostly by 1s orbitals of C, N, and O atoms, namely 25 first (lowest energy) orbitals in oxozirconium porphyrin and porphyrazine, 33 in octamethylporphyrin and 41 in phthalocyanine, were excluded ("frozen") from the TDDFT calculations.…”