Functions of bioinspired pyrrole cobalt complexes–recently developed catalytic systems of vitamin B12 related complexes and porphycene complexes–

Koide, Taro; Ono, Toshikazu; Shimakoshi, Hisashi; Hisaeda, Yoshio

doi:10.1016/j.ccr.2022.214690

Cited by 15 publications

(9 citation statements)

References 135 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…139 The Co(II) complex was reduced by NaBH 4 to produce the Co(I) complex. 139 The photoexcited state [*Co(I)] detected by sub-picosecond transient absorption spectroscopy has a lifetime of 280 ps, which was long enough for reductive dehalogenation of aryl halides such as bromobenzonitrile and iodobenzonitrile via dissociative electron transfer from *Co(I) to aryl halides (Scheme 16). 139 The E red * value (vs. NHE) of the Co(I) complex in MeOH was estimated to be ca.…”

Section: Cobalt(i) Complexesmentioning

confidence: 99%

“…139 The photoexcited state [*Co(I)] detected by sub-picosecond transient absorption spectroscopy has a lifetime of 280 ps, which was long enough for reductive dehalogenation of aryl halides such as bromobenzonitrile and iodobenzonitrile via dissociative electron transfer from *Co(I) to aryl halides (Scheme 16). 139 The E red * value (vs. NHE) of the Co(I) complex in MeOH was estimated to be ca. -1.9 V (= À2.1 V vs. Ag/AgCl), which is negative enough to reduce iodobenzonitrile (E pc vs. Ag/AgCl = À1.80 V; E pc = cathodic peak potential), bromobenzonitrile (E pc vs. Ag/AgCl = À1.81 V) and chlorobenzonitrile (E pc vs. Ag/AgCl = À1.94 V).…”

Section: Cobalt(i) Complexesmentioning

confidence: 99%

See 1 more Smart Citation

Redox reactivity of LMCT and MLCT excited states of Earth‐abundant metal complexes

Nam,

Lee,

Fukuzumi

2024

Bulletin Korean Chem Soc

View full text Add to dashboard Cite

Precious metal complexes, which act as excellent photoredox catalysts, have now being replaced by earth‐abundant metal complexes. This review focused on redox reactivity of ligand‐to‐metal charge transfer (LMCT) and metal‐to‐ligand charge transfer (MLCT) excited states of earth‐abundant metal complexes. Iron complexes with strongly σ‐donating NHC‐ligands (NHC = N‐heterocyclic carbene) has emerged, featuring long lived LMCT excited states due to a significantly increased barrier for deactivation via metal centered states. A Fe(III)‐NHC complex acts as an effective photoredox catalyst for various photocatalytic redox reactions. Although manganese(IV)‐oxo complexes have no long‐lived excited states (τ < < 1 ns). Once acids such as Sc(OTf)3 and HOTf are bound to the oxo moiety of Mn(IV)‐oxo complexes, the photoexcitation of acid‐bound Mn(IV)‐oxo complexes resulted in formation of the excited states with microseconds lifetimes, which are capable of oxidation of substrates including benzene to phenol. Photoexcited states of Mn(III), Mn(II) and Mn(I) complexes act as photoreductants to reduce substrates including O2. On the other hand, photoexcited states of Co(IV) and Co(III) complexes act as photooxidants, whereas those of Co(II) and Co(I) complexes act as photoreductants. With regard to the excited state lifetime, [Cr(tpe)2]3+ (tpe = 1,1,1‐tris(pyrid‐2‐yl)ethane) exhibited the longest luminescence lifetime (τ = 4500 μs), acting as an effective photoredox catalyst for photocatalytic redox reactions. The LMCT state of a Cr(0) complex acts as a super photoreductant. Thus, LMCT and MLCT excited states of earth‐abundant metal complexes are utilized as strong photooxidants and photoreductants, respectively.

show abstract

Section: Cobalt(i) Complexesmentioning

confidence: 99%

Section: Cobalt(i) Complexesmentioning

confidence: 99%

Redox reactivity of LMCT and MLCT excited states of Earth‐abundant metal complexes

Nam,

Lee,

Fukuzumi

2024

Bulletin Korean Chem Soc

View full text Add to dashboard Cite

show abstract

“…4 Breathing difficulty, tiredness, and atrophic gastritis are the common symptoms of Vit-B 12 deficiency in the human body. 5 Severe Vit-B 12 deficiency can result in serious disorders, such as megaloblastic and pernicious anemia, neurological disorders, and immunological disorders. 6 The development of techniques to measure vitamin B 12 levels is critical because of the global problem of a lack of sophisticated methods for the detection of vitamin B 12 .…”

Section: Introductionmentioning

confidence: 99%

Biogenic-magnesium oxide nanoparticles from Bauhinia variegata (Kachnar) flower extract: a sustainable electrochemical approach for vitamin-B₁₂ determination in real fruit juice and milk

Shaktawat,

Verma,

Singh

et al. 2024

Sustainable Food Technol.

View full text Add to dashboard Cite

show abstract

“…Cobalamins (Cbls; Figure 1 A) are the most ubiquitous cobalt complexes in nature. The catalytic behavior of Cbls has been characterized in numerous systems [ 11 , 12 , 13 ]. However, the application of corrinoids in the activation of oxidants found limited attention.…”

Section: Introductionmentioning

confidence: 99%

Aquacobalamin Accelerates Orange II Destruction by Peroxymonosulfate via the Transient Formation of Secocorrinoid: A Mechanistic Study

Dereven’kov

Sakharova

Osokin

et al. 2022

IJMS

View full text Add to dashboard Cite

Besides its use in medicine, vitamin B12 (cobalamin) and its derivatives have found in numerous applications as catalysts. However, studies related to the activation of oxidants via cobalamin are scant. In this work, we showed how the addition of aquacobalamin (H2OCbl) accelerates the destruction of azo-dye Orange II by peroxymonosulfate (HSO5−) in aqueous solutions. In neutral and weakly alkaline media, the process is initiated by the modification of the corrin macrocycle with HSO5−, which requires the preliminary deprotonation of the aqua-ligand in H2OCbl to give hydroxocobalamin, producing 5,6-dioxo-5,6-secocobalamin or its isomer (14,15-dioxo-14,15-secocobalamin). In acidic solutions, where the concentration of hydroxocobalamin is negligible, the formation of dioxo-seco-species is not observed, and the reaction between H2OCbl and HSO5− results in slow chromophore bleaching. Using terephthalic acid, we demonstrated the formation of hydroxyl radicals in the mixture of H2OCbl with HSO5-, whereas the generation of sulfate radicals was proved by comparing the effects of ethanol and nitrobenzene on Orange II destruction using the H2OCbl/HSO5− system. The reaction mechanism includes the binding of HSO5− to the Co(III) ion of dioxo-secocobalamin, which results in its deprotonation and the labilization of the O-O bond, leading to the formation of sulfate and hydroxyl radicals which further react with Orange II.

show abstract

Functions of bioinspired pyrrole cobalt complexes–recently developed catalytic systems of vitamin B12 related complexes and porphycene complexes–

Cited by 15 publications

References 135 publications

Redox reactivity of LMCT and MLCT excited states of Earth‐abundant metal complexes

Redox reactivity of LMCT and MLCT excited states of Earth‐abundant metal complexes

Biogenic-magnesium oxide nanoparticles from Bauhinia variegata (Kachnar) flower extract: a sustainable electrochemical approach for vitamin-B₁₂ determination in real fruit juice and milk

Aquacobalamin Accelerates Orange II Destruction by Peroxymonosulfate via the Transient Formation of Secocorrinoid: A Mechanistic Study

Contact Info

Product

Resources

About

Functions of bioinspired pyrrole cobalt complexes–recently developed catalytic systems of vitamin B12 related complexes and porphycene complexes–

Cited by 15 publications

References 135 publications

Redox reactivity of LMCT and MLCT excited states of Earth‐abundant metal complexes

Redox reactivity of LMCT and MLCT excited states of Earth‐abundant metal complexes

Biogenic-magnesium oxide nanoparticles from Bauhinia variegata (Kachnar) flower extract: a sustainable electrochemical approach for vitamin-B12 determination in real fruit juice and milk

Aquacobalamin Accelerates Orange II Destruction by Peroxymonosulfate via the Transient Formation of Secocorrinoid: A Mechanistic Study

Contact Info

Product

Resources

About

Biogenic-magnesium oxide nanoparticles from Bauhinia variegata (Kachnar) flower extract: a sustainable electrochemical approach for vitamin-B₁₂ determination in real fruit juice and milk