Molecular structures, and optical and magnetic properties of free-base tetrapyrazinoporphyrazine in various reduction states

Abstract

The synthesis, and spectral and structural characterization of the novel radical anion and dianion salts of free-base tetrapyrazinoporphyrazine (H2TPyzPz) as well as studies of their magnetic properties have been described.

Crystalline salts of anionic free-base tetrapyrazinoporphyrazines with alkyl-substituents or an extended π-electron system

“…29 Moreover, the singlet ground state for the H 2 TPyzPz 2− dianions was shown by DFT calculations (the singlet–triplet energy gap was calculated to be 1130 K). 29 It should be noted that salt 3 is also EPR silent, indicating the diamagnetism of deprotonated HT(PhnPyz)Pz − anions. This supports the deprotonation of the macrocycle at the formation of 3 .…”

“…[22][23][24][25][26][27] However, till now, only a few anionic compounds have been reported for pyrazine analogues of phthalocyanine, tetrapyrazinoporphyrazines (TPyzPzs). Those obtained and studied are a series of radical anion and dianion salts based on unsubstituted free-base H 2 TPyzPz, 28,29 salts of the macrocycles with acceptor (Cl, CN) substituents, 30 or an extended p-system. 31 Reduction of Fe II TPyzPzEt 8 -iron(II) octaethyltetrapyrazinoporphyrazine -by zinc dust yields crystalline complex based on {Fe II (TPyzPzEt 8 ) 4À } 2À dianions that coordinate two ZnCl 2 units on the periphery of the macrocycle.…”

“…41,42 Previously, it was found that an average difference between short and long C-N meso bonds in the H 2 TPyzPz 2À dianion (0.074-0.092 Å) is essentially greater than those for the H 2 TPyzPz À radical anions (0.009-0.011 Å) (Table 2). 29 Such a tendency is supported by DFT calculations. 28 Significant differences of 0.081 Å and 0.122 Å (Table 2) are observed between short and long C-N meso bonds in the reduced macrocycles of 1 and 2, respectively.…”

Crystal engineering of ferrocene-based charge-transfer complexes for NIR-II photothermal therapy and ferroptosis

“…Organic charge-transfer complexes (CTCs), composed of wellaligned electron donor (D) and acceptor (A), often possess unique physical properties distinguished from the parent molecules, including conductibility, paramagnetism, thermoelectricity, and luminescence [1][2][3] . These fascinating characteristics of CTCs come from their new electronic structure and aggregation state which make them ideal functional materials for optoelectronic devices 4,5 .…”

“…Organic charge-transfer complexes (CTCs), composed of a wellaligned electron donor (D) and acceptor (A), oen possess unique physical properties distinguished from the parent molecules, including conductibility, paramagnetism, thermoelectricity, and luminescence. [1][2][3] These fascinating characteristics of CTCs come from their new electronic structure and aggregation state which make them ideal functional materials for optoelectronic devices. 4,5 Besides, recent advances have demonstrated that CTCs show strong near-infrared (NIR) lightharvesting ability and a good photothermal effect due to the intense charge transfer interaction and activation of nonradiative pathways, which make CTCs one kind of promising NIR-absorbing photothermal agents (PTAs) for antitumor therapy, antibacterial and water desalination.…”