89372-90-7Relevant articles and documents
Regiospecific β-functionalization of free-base porphyrins by pseudohalogens
Zhang, Wei,Wicks, Matthew N.,Burn, Paul L.
, p. 879 - 886 (2008)
Pseudohalogens based on iodine ('I-X') can be used to regiospecifically introduce chlorine atoms or acetoxy groups onto the β-positions of meso-tetraphenylporphyrins (TPPs). TPPs and a quinoxaline derivative were reacted with iodine monochloride to give mono- or di-chlorinated porphyrins, such that when two chlorine atoms were added they were placed antipodally on the porphyrin ring. Reaction of the porphyrins with a mixture of iodine and silver acetate gave the corresponding mono- and di-acetoxylated porphyrins. The acetoxylated porphyrins could be simply transformed to the corresponding hydroxyporphyrins with subsequent oxidation with the Dess-Martin periodinane, giving a simple new route to chlorin-α-diones and bacteriochlorin- tetraones. From the products of the reactions and a UV-visible spectroscopic study, it is proposed that the reactions proceed via a single electron transfer mechanism through a porphyrin cation radical intermediate. The Royal Society of Chemistry.
Triplet photophysics of gold(III) porphyrins
Eng, Mattias P.,Ljungdahl, Thomas,Andreasson, Joakim,Martensson, Jerker,Albinsson, Bo
, p. 1776 - 1784 (2005)
Gold porphyrins are often used as electron-accepting chromophores in donor-acceptor complexes for the study of photoinduced electron transfer, and they can also be involved in triplet-triplet energy-transfer interactions with other chromophores. Since the lowest excited singlet state is very short-lived (240 fs), the triplet state is usually the starting point for the transfer reactions, and it is therefore crucial to understand its photophysics. The triplet state of various gold porphyrins has been reported to have a lifetime of around 1.5 ns at room temperature and to have a biexponential decay both in emission and in transient absorption with decay times of around 10 and 100 μs at 80 K. In this paper, the triplet photophysics of two gold porphyrins (AuIII 5,15-bis(3,5-di-terf-butylphenyl)-2,8,12,18-tetraethyl-3,7,13, 17-tetramethylporphyrin and AuIII 5,10,15,20-tetra(3,5-di-fert- butylphenyl)porphyrin) are studied by steady-state and time-resolved absorption and emission spectroscopy over a wide temperature range (4-300 K). The study reveals the existence of a dark state with an approximate lifetime of 50 ns, which was not previously observed. This state acts as an intermediate between the short-lived singlet and the triplet state manifold. In addition, we present DFT calculations, in which the core electrons of the central metal were replaced by a pseudopotential to account for the relativistic effects, which suggest that the lowest excited singlet state is an optically forbidden ligand-to-metal charge-transfer (LMCT) state. This LMCT state is an obvious candidate for the experimentally observed dark state, and it is shown to dictate the photophysical properties of gold porphyrins by acting as a gate for triplet state formation versus direct return to the ground state.
A NEW ANTINEOPLASTIC METHYLGERMANIUM(IV)PORPHYRIN
Miyamoto, T. Ken,Sugita, Norifumi,Matsumoto, Yuji,Sasaki, Yukiyoshi,Konno, Michiko
, p. 1695 - 1698 (1983)
A new highly lipophilic methylgermanium(IV)porphyrin; dimethyl-5,10,15,20-tetrakisporphynatogermanium(IV) (Abbr.MGP), has been prepared and characterized.The isolated compound showed considerable activity toward neo
Oxidative Cyclodehydrogenation Reactions with Tetraarylporphyrins
Hampel, Frank,Jux, Norbert,Martin, Max M.,Oleszak, Christoph
supporting information, p. 6758 - 6762 (2020/11/23)
The extension of the aromatic π-system of porphyrins is a powerful method to alter their optoelectronic properties. Herein, aryl substituents were fused to porphyrin cores by Scholl oxidation reactions that selectively produced mono- and doubly-fused porphyrins in yields of up to 69 %. Several different aryl substituents attached to the porphyrin were investigated with respect to their reactivity under Scholl conditions. The fused products were fully characterized, i.e., by UV/Vis absorption spectroscopy, which showed drastic changes in the electronic features. Insight into the solid-state behavior was obtained by X-ray crystallography. Our approach represents a novel option for the late-stage functionalization of porphyrin-based compounds.
Theoretical and experimental analysis of porphyrin derivatives with suitable anchoring groups for DSSC applications
Sánchez-Bojorge, Nora A.,Flores-Armendáriz, Simón,Fuentes-Montero, María E.,Ramos-Sánchez, Victor H.,Zaragoza-Galán, Gerardo,Rodríguez-Valdez, Luz M.
, p. 88 - 102 (2017/04/24)
In this contribution, different porphyrin derivatives were experimentally synthesized and theoretically analyzed using several electronic structure methods to study the geometrical and electronic properties of A4, trans-A2B2/su
