Formation and Isolation of a Four‐Electron‐Reduced Porphyrin Derivative by Reduction of a Stable 20π Isophlorin

Nickel(II) and copper(II) complexes of redoxswitchable 20π, 19π, and 18π 5,15-dialkyl-10,20-diaryl-5,15diazaporphyrins were prepared through a metal-templated cyclization method. Furthermore, the terminal silyloxy groups in the peripheral N-alkyl chains were transformed into hydroxy groups by deprotection. It is worth noting that redox reactions between the 19π and 18π systems bearing hydroxy groups caused a change in the water solubility of the diazaporphyrin chromophore.

show abstract

Synthesis of Redox‐switchable 5,15‐Dialkyl‐10,20‐diaryl‐5,15‐diazaporphyrins and Diversification of their N‐Alkyl Groups

Mutoh

Sudoh

Furukawa

et al. 2019

Asian J Org Chem

View full text Add to dashboard Cite

show abstract

Facile Redox‐Induced Aromatic–Antiaromatic Interconversion of a β‐Tetracyano‐21,23‐Dithiaporphyrin under Ambient Conditions

Yamashita

Nakajima

Honda

et al. 2020

Chemistry A European J

View full text Add to dashboard Cite

Facile redox‐induced aromatic–antiaromatic interconversions were accomplished by using β‐tetracyano‐21,23‐dithiaporphyrin (CN4S2Por). Introduced cyano groups not only increased the reduction potential of the porphyrin core but also stabilized the antiaromatic isophlorin (CN4S2Iph) by π conjugation. The reduction of CN4S2Por with hydrazine in polar solvents quantitatively affords CN4S2Iph, even under ambient conditions. CN4S2Iph retains a nearly planar conformation and exhibits considerable antiaromaticity. Aerobic oxidation of CN4S2Iph to CN4S2Por occurs in nonpolar solvents. This study was conducted to contribute to the understanding of the structure–antiaromaticity relationship.

show abstract

A Mechanistic Dichotomy in Two‐Electron Reduction of Dioxygen Catalyzed by N,N’‐Dimethylated Porphyrin Isomers

Suzuki

Kotani

Ishizuka

et al. 2020

Chemistry A European J

Self Cite

View full text Add to dashboard Cite

Selective two‐electron reduction of dioxygen (O2) to hydrogen peroxide (H2O2) has been achieved by two saddle‐distorted N,N’‐dimethylated porphyrin isomers, an N21,N’22‐dimethylated porphyrin (anti‐Me2P) and an N21,N’23‐dimethylated porphyrin (syn‐Me2P) as catalysts and ferrocene derivatives as electron donors in the presence of protic acids in acetonitrile. The higher catalytic performance in an oxygen reduction reaction (ORR) was achieved by anti‐Me2P with higher turnover number (TON=250 for 30 min) than that by syn‐Me2P (TON=218 for 60 min). The reactive intermediates in the catalytic ORR were confirmed to be the corresponding isophlorins (anti‐Me2Iph or syn‐Me2Iph) by spectroscopic measurements. The rate‐determining step in the catalytic ORRs was concluded to be proton‐coupled electron‐transfer reduction of O2 with isophlorins based on kinetic analysis. The ORR rate by anti‐Me2Iph was accelerated by external protons, judging from the dependence of the observed initial rates on acid concentrations. In contrast, no acceleration of the ORR rate with syn‐Me2Iph by external protons was observed. The different mechanisms in the O2 reduction by the two isomers should be derived from that of the arrangement of hydrogen bonding of a O2 with inner NH protons of the isophlorins.

show abstract

scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.

Contact Info

customersupport@researchsolutions.com

10624 S. Eastern Ave., Ste. A-614

Henderson, NV 89052, USA

Blog Terms and Conditions API Terms Privacy Policy Contact Cookie Preferences Do Not Sell or Share My Personal Information

Made with 💙 for researchers

Part of the Research Solutions Family.

Formation and Isolation of a Four‐Electron‐Reduced Porphyrin Derivative by Reduction of a Stable 20π Isophlorin

Cited by 5 publications

References 43 publications

Synthesis of Redox‐switchable 5,15‐Dialkyl‐10,20‐diaryl‐5,15‐diazaporphyrins and Diversification of their N‐Alkyl Groups

Synthesis of Redox‐switchable 5,15‐Dialkyl‐10,20‐diaryl‐5,15‐diazaporphyrins and Diversification of their N‐Alkyl Groups

Facile Redox‐Induced Aromatic–Antiaromatic Interconversion of a β‐Tetracyano‐21,23‐Dithiaporphyrin under Ambient Conditions

A Mechanistic Dichotomy in Two‐Electron Reduction of Dioxygen Catalyzed by N,N’‐Dimethylated Porphyrin Isomers

Contact Info

Product

Resources

About