One-pot synthesis of functionalized, highly substituted porphodimethenes

Bischoff, Ines; Feng, Xiangdong; Senge, Ma­thias O.

doi:10.1016/s0040-4020(01)00486-0

Cited by 40 publications

(42 citation statements)

References 27 publications

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“…The steric strain imposed on the systems also gives rise to novel, porphyrin atypical reactions -notably for porphyrins with very large ruf distortions, and has led to routes for the formation of porphodimethenes (''calixphyrins''). 97,98 In contrast, the more planar porphyrins, or sad distorted porphyrins, undergo ''standard'' porphyrin reactions. This increased reactivity is clearly a consequence of the steric strain at the meso positions.…”

Section: 31mentioning

confidence: 99%

Conformational control of cofactors in nature – the influence of protein-induced macrocycle distortion on the biological function of tetrapyrroles

2015

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Tetrapyrrole-containing proteins are one of the most fundamental classes of enzymes in nature and it remains an open question to give a chemical rationale for the multitude of biological reactions that can be catalyzed by these pigmentprotein complexes. There are many fundamental processes where the same (i.e., chemically identical) porphyrin cofactor is involved in chemically quite distinct reactions. For example, heme is the active cofactor for oxygen transport and storage (hemoglobin, myoglobin) and for the incorporation of molecular oxygen in organic substrates (cytochrome P 450 ). It is involved in the terminal oxidation (cytochrome c oxidase) and the metabolism of H 2 O 2 (catalases and peroxidases) and catalyzes various electron transfer reactions in cytochromes. Likewise, in photosynthesis the same chlorophyll cofactor may function as a reaction center pigment (charge separation) or as an accessory pigment (exciton transfer) in light harvesting complexes (e.g., chlorophyll a). Whilst differences in the apoprotein sequences alone cannot explain the often drastic differences in physicochemical properties encountered for the same cofactor in diverse protein complexes, a critical factor for all biological functions must be the close structural interplay between bound cofactors and the respective apoprotein in addition to factors such as hydrogen bonding or electronic effects. Here, we explore how nature can use the same chemical molecule as a cofactor for chemically distinct reactions using the concept of conformational flexibility of tetrapyrroles. The multifaceted roles of tetrapyrroles are discussed in the context of the current knowledge on distorted porphyrins. Contemporary analytical methods now allow a more quantitative look at cofactors in protein complexes and the development of the field is illustrated by case studies on hemeproteins and photosynthetic complexes. Specific tetrapyrrole conformations are now used to prepare bioengineered designer proteins with specific catalytic or photochemical properties.

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Section: 31mentioning

confidence: 99%

Conformational control of cofactors in nature – the influence of protein-induced macrocycle distortion on the biological function of tetrapyrroles

2015

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“…Reaction with PhLi gave a pink product in small amounts that could not be isolated. The only example reported in the literature was the reaction with an electrophile when Grigg et al serendipitously prepared (2,3,7,8,12,13,17,palladium from 3 by reaction with trifluoromethyl sulfonate. 16 The meso monosubstituted Pd(II)OEP complexes showed an increased reactivity toward RLi reagents (Scheme 3).…”

Section: Meso Disubstituted Porphyrinsmentioning

confidence: 99%

“…2, 3,7,8,12,13,17,29 and its nickel(II) complex 2 were synthesized according to standard procedures. The synthesis of the Pd(II) complex 50-52 will be given elsewhere.…”

Section: Starting Materialsmentioning

confidence: 99%

Highly substituted 2,3,7,8,12,13,17,18-octaethylporphyrins with meso aryl residues

et al. 2010

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a b s t r a c tHighly substituted porphyrin-bearing meso aryl groups are useful compounds for optical applications and for studies on the interrelationship between the substituent pattern, macrocycle conformation and physical properties. They serve as biomimetic models for the function of tetrapyrroles in nature and help to elucidate modulation of cofactor properties through conformational effects. Using a sequence of lithium organic substitution reactions the synthesis of novel free base 5,10-A 2 -and 5,10-AB-2,3,7,8,12,13,17,18-octaethylporphyrins bearing donating groups such as -OMe and -NMe 2 on the arylsubstituent was achieved. Larger aromatic residues (1-naphthyl, 9-anthracenyl and 9-phenanthrenyl) could be introduced into the macrocycle system as well, and these systems were used for the preparation of highly substituted porphyrins with a mixed substituent pattern. Using phenanthrenyl derivatives, the complete series of meso phenanthrenyl substituted octaethylporphyrins was successfully synthesized and the palladium complexes were prepared for photophysical investigations. Structural studies clearly showed the influence of individual substituents on the conformation of the tetrapyrrole macrocycle and conformational analyses revealed the variation of the underlying distortion modes depending on the type and arrangement of the meso substituents.

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“…When coupling was attempted using Zn(II) porphyrins, for the most part only starting material remained, and anthracenylporphyrins were isolated in low yield. Possibly this is due to the more ruffled conformation of Ni(II) meso-arylporphyrins [26], which gives the bulky anthracenyl residue easier access to the meso position [27]. For meso-alkylporphyrins the situation was reversed with both the free base and the zinc(II) complex giving good yields (e. g. compounds 14 and 15).…”

Section: Anthracenylporphyrins Via Suzuki Cross Couplingmentioning

confidence: 99%

“…Overall, this reaction gave a good yield of 14 % for compound 25. Again, the free base was converted into the respective zinc(II) (26) and nickel(II) (27) complexes. The alternative combination of 5-(anthracen-9-yl)dipyrromethane and hexanal worked as well.…”

Section: Condensation Reactionsmentioning

confidence: 99%

Anthracenylporphyrins

Davis

Senge

Locos

2010

Zeitschrift Für Naturforschung B

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We report the synthesis and characterization of meso-anthracenylporphyrins with zinc and nickel metal centers. A variety of novel aryl and alkyl meso-substituted anthracenylporphyrins were synthesized via step-wise Suzuki cross-coupling reactions using anthracenyl boronates. This method was compared to standard syntheses based on condensation reactions to yield anthracenylporphyrins of the A 2 B 2 -and A 3 B-type. The work was complemented by the synthesis of a number of the functionalized anthracene derivatives via Suzuki couplings. Selected systems were subjected to single-crystal X-ray analysis which revealed an unusual close packing for nickel(II) anthracenylporphyrins.

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One-pot synthesis of functionalized, highly substituted porphodimethenes

Cited by 40 publications

References 27 publications

Conformational control of cofactors in nature – the influence of protein-induced macrocycle distortion on the biological function of tetrapyrroles

Conformational control of cofactors in nature – the influence of protein-induced macrocycle distortion on the biological function of tetrapyrroles

Highly substituted 2,3,7,8,12,13,17,18-octaethylporphyrins with meso aryl residues

Anthracenylporphyrins

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