Thiadiazole-containing expanded heteroazaporphyrinoids: a gas-phase electron diffraction and computational structural study

Abstract

The gas-phase molecular structure of a thiadiazole-containing expanded heteroazaporphyrinoid (C42H39N15S3) 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. The molecule has an equilibrium structure of C3h symmetry with a planar macrocycle and the thiadiazole rings oriented in such a way that the sulfur atoms point outwards from the inner cavity. The unsubstituted macrocycle (C30H15N15S3) has been studied by DFT computations. An algorithm for building a complete set of internal coordinates, used in the computation of vibrational corrections, is also described.

Synthesis of Thiadiazole Hemihexaporphyrazine Bearing iso-Propyloxy Groups and its Trinuclear NiII Complex

“…2, 3,14,15,26,36:12,17:24,10:19,22:31,p,2,4,9,11,12,14,19,21,22,24,4,6,8,10,12,14,16,18,20,22,24,26,28,4. 3,6-Diisopropyloxyphthalonitrile (6, 244 mg, 1.0 mmol) and 2,5-diamino-1,3,4-thiadiazole, (7, 116 mg, 1.0 mmol) were dissolved in dry isopropanol (8 ml) at reflux.…”

“…Its expanded macrocyclic cavity with two metal ions inside was constructed by the dimerization of metal complex of opened trimeric intermediate of two diiminoisoindoline and one triazole subunits (BAB). Later, another expanded metal-free 30 π-electron hemiporphyrazine 2 of ABABABtype has been communicated [16] as a product of the crossover condensation of three 2,5-diamino-1,3,4-thiadiazole and three substituted diiminoisoindoline. This macrocycle is considered to be a hexaphyrin analogue where its subunits are bonded via six aza-bridges and three pyrrolic rings are replaced by three thiadiazoles.…”

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.…”

Homotrinuclear Сomplexes of [30]Trithiadodecaazahexaphyrine with Transition Metals: Ni(II), Cu(II) and Mn(II)

“…[7][8][9] Among expanded compounds, Mc's of ABABAB-type (hemihexaphyrazine, H 3 Hhp) containing six consecutively interlinked 1,3,4-thiadiazole (A) and isoindole (B) subunits bridged by nitrogen atoms [10,11] induce a particular interest. Indeed, various substituted macroheterocyclic compounds of this type were synthesized to date [12][13][14][15][16][17][18] and their structures were confirmed by gas electron diffraction (GED) [19,20] and single crystal X-ray diffraction [21] methods. It was established that compounds of this type have a nonaromatic macrocyclic backbone containing 30 carbon and nitrogen atoms which form an expanded coordination cavity compared to that of porphyrins and phthalocyanines.…”