pyridine-derivatives | Page 851 of 2491

Feng, Xiaoxia et al. published new experimental results with the assistance of cas: 100-54-9

3-Cyanopyridine(cas: 100-54-9) has been shown to have a number of pharmacological effects: it inhibits the production of prostaglandin E2 and nitric oxide in congestive heart failure patients; it prevents the formation of diazonium salt from benzene and nitrogen dioxide; it inhibits the growth of tumor cell lines; and it protects mice from radiation injury by scavenging reactive oxygen species. Recommanded Product: 3-Cyanopyridine

Feng, Xiaoxia;Li, Dong;Liang, Wenqing;Ruan, Ting;Jiang, Guibin published 《Recognition and prioritization of chemical mixtures and transformation products in Chinese estuarine waters by suspect screening analysis》 in 2021. The article was appeared in 《Environmental Science & Technology》. They have made some progress in their research.Recommanded Product: 3-Cyanopyridine The article mentions the following:

Chem. mixtures in surface waters could have significant impacts on exposure risks to human beings and pollution stress to aquatic system. By suspect screening anal. of high-resolution mass spectrometry data, occurrence, and compositions of ToxCast chems. were investigated in grab estuarine water samples from a combination of 20 rivers that represents approx. 70% of the total river flow discharge along the east coast of China. In total, 59 ToxCast chems. in seven use categories were identified, in which pesticides, intermediates, and pharmaceuticals were the abundant analogs. Significant differences in pollutant composition profiles were noticed, which possibly reflected singular release pattern and geog.-relevant usage preference (especially for herbicides and fungicides in the pesticide category). With the aid of tentative quant./semiquant. measurement, essential contributors to the cumulative pollutant mass discharges and aquatic acute toxicity potentials were focused onto few particular chems. Existence of transformation products was further explored, which indicated that the fates of the selected parent ToxCast chems. could be influenced by dominating transformation reactions (e.g., N-dealkylation and hydroxylation) and possible environmental factors (i.e., microbial activity). The results emphasize the necessity of suspect screening anal. for assessing the influence of terrestrial emissions of pollutants to the surrounding environment. And 3-Cyanopyridine (cas: 100-54-9) was used in the research process.

Reference:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Cas: 80-32-0 | Hu, Jingrunpublished an article in 2022

4-Amino-N-(6-chloropyridazin-3-yl)benzenesulfonamide(cas: 80-32-0) can be introduced in the drinking water to fabricate aqueous liquid formulations for combating bacterial and protozoal in animals.Computed Properties of C10H9ClN4O2S Besides, sulfachloropyridazine associated to tripelennamine hydrocholoride has been demonstrated to function as an anti-stress agent in poultry after vaccinations.

Computed Properties of C10H9ClN4O2S《Comparison and prioritization of antibiotics in a reservoir and its inflow rivers of Beijing, China》 was published in 2022. The authors were Hu, Jingrun;Qi, Dianqing;Chen, Qian;Sun, Weiling, and the article was included in《Environmental Science and Pollution Research》. The author mentioned the following in the article:

The occurrence of antibiotics in drinking water resources, like reservoirs, is of considerable concern due to their potential risks to ecosystem, human health, and antimicrobial resistance development. Here, we quantified 83 antibiotics in water and sediments of wet and dry seasons from the Miyun reservoir and its inflow rivers in Beijing, China. Twenty-four antibiotics were detected in water with concentrations of ND-11.6 ng/L and 19 antibiotics were observed in sediments with concentrations of ND-6.50 ng/g. Sulfonamides (SAs) were the dominated antibiotics in water in two seasons. SAs and quinolones (QNs) in wet season and macrolides (MLs) and QNs in dry season predominated in sediments. The reservoir and inflow rivers showed significant differences in antibiotic concentrations and compositions in water and sediments. As an important input source of reservoir, the river water showed significantly higher total antibiotic concentrations than those in the reservoir. In contrast, the reservoir sediments are the sink of antibiotics, and had higher total antibiotic concentrations compared with rivers. A prioritization approach based on the overall risk scores and detection frequencies of antibiotics was developed, and 3 (sulfaguanidine, anhydroerythromycin, and sulfamethoxazole) and 5 (doxycycline, sulfadiazine, clarithromycin, roxithromycin, and flumequine) antibiotics with high and moderate priority, resp., were screened. The study provides a comprehensive insight of antibiotics in the Miyun Reservoir and its inflow rivers, and is significant for future monitoring and pollution mitigation of antibiotics. The experimental procedure involved many compounds, such as 4-Amino-N-(6-chloropyridazin-3-yl)benzenesulfonamide (cas: 80-32-0) .

Reference:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Shang, Yu-Ting et al. published new progress in experiments with the help of cas: 100-54-9

Safety of 3-Cyanopyridine《High-throughput screening of a nicotinate dehydrogenase producing Pseudomonas putida mutant for efficient biosynthesis of 6-hydroxynicotinic acid》 was published in 2021. The authors were Shang, Yu-Ting;Qin, Jiufu;Gong, Jin-Song;Wang, Zi-Kai;Li, Heng;Li, Hui;Shi, Jin-Song;Xu, Zheng-Hong, and the article was included in《Molecular Catalysis》. The author mentioned the following in the article:

A nicotinate dehydrogenase producing strain was isolated and identified to be Pseudomonas putida, which could bio-transform nicotinic acid into 6-hydroxynicotinic acid. The activity of nicotinate dehydrogenase towards nicotinic acid could reach up to 1.11 U/mL and the yield of 6-hydroxynicotinic acid accumulated to 176 g/L within 30 h with a space time yield of 1.36 g/(g·h). In order to further improve its catalytic potential, a mutant library was constructed through atm. and room temperature plasma (ARTP) and rapidly screened by a high-throughput screening strategy, which obtained a mutant strain mut-5 with activity of 2.68 U/mL. Via developing a nitrilase-nicotinate dehydrogenase enzymic cascade system, 54.5 g/L 6-hydroxynicotinic acid could be obtained within 585 min with 3-cyanopyridine as the substrate, which would further reduce the production costs. The results indicated that the nicotinate dehydrogenase (sep. or combining with nitrilase) could serve as a superior catalyst for 6-hydroxynicotinic acid production To our knowledge, the nicotinate dehydrogenase activity reported in this study was the highest level in literature to date. The experimental procedure involved many compounds, such as 3-Cyanopyridine (cas: 100-54-9) .

Reference:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Van Laethem, Thomas et al. published new experimental results with the assistance of cas: 100-54-9

3-Cyanopyridine(cas: 100-54-9) is an antimicrobial agent that can be used in the treatment of infectious diseases.Product Details of 100-54-9 It has been shown to be effective against a variety of bacteria, including methicillin-resistant Staphylococcus aureus (MRSA) and Streptococcus pneumoniae.

Product Details of 100-54-9《A pharmaceutical-related molecules dataset for reversed-phase chromatography retention time prediction built on combining pH and gradient time conditions》 was published in 2022. The authors were Van Laethem, Thomas;Kumari, Priyanka;Hubert, Philippe;Fillet, Marianne;Sacre, Pierre-Yves;Hubert, Cedric, and the article was included in《Data in Brief》. The author mentioned the following in the article:

There is a rising interest in the modeling and predicting of chromatog. retention. The progress towards more complex and comprehensive models emphasized the need for broad reliable datasets. The present dataset comprises small pharmaceutical compounds selected to cover a wide range in terms of physicochem. properties that are known to impact the retention in reversed-phase liquid chromatog. Moreover, this dataset was analyzed at five pH with two gradient slopes. It provides a reliable dataset with a diversity of conditions and compounds to support the building of new models. To enhance the robustness of the dataset, the compounds were injected individually, and each sequence of injections included a quality control sample. This unambiguous detection of each compound as well as a systematic anal. of a quality control sample ensured the quality of the reported retention times. Moreover, three different liquid chromatog. systems were used to increase the robustness of the dataset. And 3-Cyanopyridine (cas: 100-54-9) was used in the research process.

Reference:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Explore more uses of cas: 80-32-0 | ACS ES&T Water

4-Amino-N-(6-chloropyridazin-3-yl)benzenesulfonamide(cas: 80-32-0) is a sulfonamide antibiotic that is usually used as antibacterial anti-inflammatory drug, which has been applied in the treatment of acute urinary tract infections in childhood.Related Products of 80-32-0Due to its antibiotic activity, this chemical has been selected as an ingredient to prepare antibacterial composition.

Yang, Lei;Wu, Xiaona;Chen, Xiaoyu;Chen, Fei;Zheng, Xiaona;Song, Qinan;Liu, Xiang;Li, Miao published 《Synergistic Removal of Nutrient Pollutants and Pharmaceutical and Personal Care Products (PPCPs) from Contaminated Groundwater: Macro- and Microelements and Microorganisms》. The research results were published in《ACS ES&T Water》 in 2022.Related Products of 80-32-0 The article conveys some information:

The synergistic removal performance of nutrient pollutants and pharmaceutical and personal care products (PPCPs) from contaminated groundwater, and the biogeochem. interactions of macro- and microelements-contaminants-microorganisms were further studied. The electrolysis-zeolite/basalt system proved to achieve better synergistic removal performance than all other purification systems considered, reaching average removal efficiencies of 85.8% for nutrient pollutants and 74.7% for PPCPs. Electrolysis not only enhanced the abundance and distribution of MOB and DNB, but also promoted the production of microelements Fe³⁺ (0.1 ± 0.1 mg/L) and Zn²⁺ (0.3 ± 0.3 mg/L). Macroelements Ca²⁺ and Mg²⁺ increased by 27.8 ± 2.7 and 16.5 ± 9.6 mg/L, resp., which significantly stimulated the activities of function microbials. Microelements Fe3+ exchanged from zeolite, Mn²⁺ from basalt, and Cu²⁺ from groundwater itself were crucial for enzyme activity. Meanwhile, Mn²⁺ was co-regulated by oxidation-reduction processes and ion-exchange strength. Thus, the electrolysis-zeolite/basalt system is a promising technol. for synergistic nutrient pollutant and PPCP removal from contaminated groundwater, especially in dispersive water supplied in the countryside of China.4-Amino-N-(6-chloropyridazin-3-yl)benzenesulfonamide (cas: 80-32-0) were involved in the experimental procedure.

Reference:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

New progress of cas: 80-32-0 | Journal of Chromatography A 2021

4-Amino-N-(6-chloropyridazin-3-yl)benzenesulfonamide(cas: 80-32-0) is a sulfonamide antibiotic that is usually used as antibacterial anti-inflammatory drug, which has been applied in the treatment of acute urinary tract infections in childhood.Recommanded Product: 80-32-0Due to its antibiotic activity, this chemical has been selected as an ingredient to prepare antibacterial composition.

Ji, Baocheng;Zhao, Wenhao;Xu, Xu;Han, Yu;Jie, Mingsha;Xu, Gaigai;Bai, Yanhong published 《Development of a modified quick, easy, cheap, effective, rugged, and safe method based on melamine sponge for multi-residue analysis of veterinary drugs in milks by ultra-performance liquid chromatography tandem mass spectrometry》. The research results were published in《Journal of Chromatography A》 in 2021.Recommanded Product: 80-32-0 The article conveys some information:

The purpose of this study was to develop a modified QuEChERS method based on melamine sponge for rapid determination of multi-class veterinary drugs in milks by UPLC-MS/MS. Through simple infiltration and extrusion, fast and convenient matrix purification could be achieved within several seconds, and there was no need of extra phase separation operations. Good linearity with correlation coefficient (R2) ≥0.999 was obtained for all drugs in the range of 2∼500μg·kg-1. The obtained matrix effects were within ±20% for all monitored drugs. The recoveries of all monitored drugs ranged from 60.7% to 116.0% at three spiked levels (50, 100, and 200μg·kg-1), with relative standard deviations less than 7.4%. Comparatively low LODs and LOQs were obtained in the ranges of 0.1∼3.8μg·kg-1 and 0.2∼6.3μg·kg-1, resp. Compared with conventional purification adsorbents, melamine sponge yielded an equal or higher purification performance with matrix removal rate as high as 52.5% and acceptable recoveries in range of 60%-120% for all monitored drugs. The satisfactory results have demonstrated the good potential of melamine sponge in matrix purification for rapid determination of multiclass residues in food safety. The experimental procedure involved many compounds, such as 4-Amino-N-(6-chloropyridazin-3-yl)benzenesulfonamide (cas: 80-32-0) .

4-Amino-N-(6-chloropyridazin-3-yl)benzenesulfonamide(cas: 80-32-0) is a sulfonamide antibiotic that is usually used as antibacterial anti-inflammatory drug, which has been applied in the treatment of acute urinary tract infections in childhood.Recommanded Product: 80-32-0Due to its antibiotic activity, this chemical has been selected as an ingredient to prepare antibacterial composition.

Reference:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Learn more about cas: 100-54-9 | Chemical Communications (Cambridge, United Kingdom) 2022

3-Cyanopyridine(cas: 100-54-9) is an antimicrobial agent that can be used in the treatment of infectious diseases.Safety of 3-Cyanopyridine It has been shown to be effective against a variety of bacteria, including methicillin-resistant Staphylococcus aureus (MRSA) and Streptococcus pneumoniae.

Safety of 3-Cyanopyridine《Palladium-catalyzed synthesis of nitriles from N-phthaloyl hydrazones》 was published in 2022. The authors were Ano, Yusuke;Higashino, Masaya;Yamada, Yuki;Chatani, Naoto, and the article was included in《Chemical Communications (Cambridge, United Kingdom)》. The author mentioned the following in the article:

The Pd-catalyzed transformation of N-phthaloyl hydrazones into nitriles RC≡N [R = 3-pyridyl, 4-MeC₆H₄, 2-naphthyl, etc.] and R(Me)C=CHC≡N involving the cleavage of an N-N bond was reported. The use of N-heterocyclic carbene as a ligand was essential for the success of the reaction. N-Phthaloyl hydrazones prepared from aromatic aldehydes or cyclobutanones were applicable to this transformation, which gaves aryl nitriles RC≡N or alkenyl nitriles R(Me)C=CHC≡N, resp.3-Cyanopyridine (cas: 100-54-9) were involved in the experimental procedure.

Reference:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Cas: 80-32-0 was involved in experiment | Journal of Separation Science 2022

4-Amino-N-(6-chloropyridazin-3-yl)benzenesulfonamide(cas: 80-32-0) can be introduced in the drinking water to fabricate aqueous liquid formulations for combating bacterial and protozoal in animals.Application In Synthesis of 4-Amino-N-(6-chloropyridazin-3-yl)benzenesulfonamide Besides, sulfachloropyridazine associated to tripelennamine hydrocholoride has been demonstrated to function as an anti-stress agent in poultry after vaccinations.

Zhang, Yue;Li, Yang;Liu, Xiaoxia;Sun, Ying published 《Determination of multiple antibiotics in agricultural soil using a quick, easy, cheap, effective, rugged, and safe method coupled with ultra-high performance liquid chromatography-tandem mass spectrometry》 in 2022. The article was appeared in 《Journal of Separation Science》. They have made some progress in their research.Application In Synthesis of 4-Amino-N-(6-chloropyridazin-3-yl)benzenesulfonamide The article mentions the following:

In this study, we combined ultra-high performance liquid chromatog. with tandem mass spectrometry to establish a quick, easy, cheap, effective, rugged, and safe method of detecting 21 target antibiotics in agricultural soil samples. Antibiotics were extracted with mixed solvents consisting of EDTA disodium salt dihydrate and phosphoric acid citric acid buffer and acetonitrile which were purified with octadecylsilyl as an adsorbent and anhydrous sodium sulfate as a desiccant. This method was able to effectively extract all of the target antibiotics from agricultural soils, with recovery efficiencies ranging from 55 to 108% and limits of detection between 0.09-0.68μg/kg. We also validated this new method for selectivity, sensitivity, and reliability of detecting multiple antibiotics in 12 samples. Considering the potential environmental and public health effects of antibiotics in agricultural soils, our new method can help analyze the degree of antibiotic contamination and provide valuable information for soil quality and risk assessment.4-Amino-N-(6-chloropyridazin-3-yl)benzenesulfonamide (cas: 80-32-0) were involved in the experimental procedure.

4-Amino-N-(6-chloropyridazin-3-yl)benzenesulfonamide(cas: 80-32-0) can be introduced in the drinking water to fabricate aqueous liquid formulations for combating bacterial and protozoal in animals.Application In Synthesis of 4-Amino-N-(6-chloropyridazin-3-yl)benzenesulfonamide Besides, sulfachloropyridazine associated to tripelennamine hydrocholoride has been demonstrated to function as an anti-stress agent in poultry after vaccinations.

Reference:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Hylland, Knut T. team published research on Dalton Transactions in 2022 | 5315-25-3

Related Products of 5315-25-3, 2-Bromo-6-methylpyridine (2BMPy) is a bromopyridine derivative. It is formed when 2-chloro-6-methylpyridine is heated with bromotrimethylsilane. Its synthesis from various methods have been reported.
2-Bromo-6-methylpyridine is a building block in the preparation of nitrogen containing heterocyclic compounds.
2-Bromo-6-methylpyridine is an organic compound that belongs to the group of pyridinium halides. It is soluble in common solvents such as water, ethanol, and acetone. 2BMPy has been shown to act as a glutamate receptor antagonist and has been used in the study of glutamate receptors, including their subtypes. This chemical has also been shown to have antioxidant properties and can be used in the prevention of atherosclerosis., 5315-25-3.

The critical parameters of pyridine are pressure 6.70 MPa, temperature 620 K and volume 229 cm3·mol−1. 5315-25-3, formula is C6H6BrN, Name is 2-Bromo-6-methylpyridine. In the temperature range 340–426 °C its vapor pressure p can be described with the Antoine equation.. Related Products of 5315-25-3.

Hylland, Knut T.;Schmidtke, Inga L.;Wragg, David S.;Nova, Ainara;Tilset, Mats research published 《 Synthesis of substituted (N,C) and (N,C,C) Au(III) complexes: the influence of sterics and electronics on cyclometalation reactions》, the research content is summarized as follows. Cyclometalated Au(III) complexes are of interest due to their catalytic, medicinal, and photophys. properties. Herein, we describe the synthesis of derivatives of the type [(N-C)Au(O₂CCF₃)₂] and [(N-C-C)Au(O₂CCF₃)] by a cyclometalation route (N-C, N-C-C = chelating 2-arylpyridine ligands). The scope of the synthesis is explored by substituting the 2-arylpyridine core with electron donor or acceptor substituents at one or both rings. Notably, a variety of functionalized Au(III) complexes can be obtained in one step from the corresponding ligand and Au(OAc)₃, eliminating the need for organomercury intermediates, which is commonly reported for similar syntheses. The influence of substituents in the ligand backbone on the resulting complexes was assessed using DFT calculations, ¹⁵N NMR spectroscopy and single-crystal X-ray diffraction anal. A correlation between the electronic properties of the (N-C) ligands and their ability to undergo cyclometalation was found from exptl. studies combined with natural charge anal., suggesting the cyclometalation at Au(III) to take place via an electrophilic aromatic substitution-type mechanism. The formation of Au(III) pincer complexes from tridentate (N-C-C) ligands was investigated by synthesis and DFT calculations, in order to assess the feasibility of C(sp³)-H bond activation as a synthetic pathway to (N-C-C) cyclometalated Au(III) complexes. It was found that C(sp³)-H bond activation is feasible for ligands containing different alkyl groups (iso-Pr and ethyl), although the C-H activation is less energetically favored compared to a ligand containing tert-Bu groups.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Hyun, Sung-Min team published research on Inorganic Chemistry in 2021 | 5315-25-3

5315-25-3, 2-Bromo-6-methylpyridine (2BMPy) is a bromopyridine derivative. It is formed when 2-chloro-6-methylpyridine is heated with bromotrimethylsilane. Its synthesis from various methods have been reported.
2-Bromo-6-methylpyridine is a building block in the preparation of nitrogen containing heterocyclic compounds.
2-Bromo-6-methylpyridine is an organic compound that belongs to the group of pyridinium halides. It is soluble in common solvents such as water, ethanol, and acetone. 2BMPy has been shown to act as a glutamate receptor antagonist and has been used in the study of glutamate receptors, including their subtypes. This chemical has also been shown to have antioxidant properties and can be used in the prevention of atherosclerosis., COA of Formula: C6H6BrN

Pyridine is colorless, but older or impure samples can appear yellow. 5315-25-3, formula is C6H6BrN, Name is 2-Bromo-6-methylpyridine. The pyridine ring occurs in many important compounds, including agrochemicals, pharmaceuticals, and vitamins. Historically, pyridine was produced from coal tar. COA of Formula: C6H6BrN.

Hyun, Sung-Min;Reid, Kaleb A.;Vali, Shaik Waseem;Lindahl, Paul A.;Powers, David C. research published 《 Cis-divacant octahedral Fe(II) in a dimensionally reduced family of 2-(Pyridin-2-yl)pyrrolide complexes》, the research content is summarized as follows. Four-coordinate transition-metal complexes can adopt a diverse array of coordination geometries, with square planar and tetrahedral coordination being the most prevalent. Previously, we reported the synthesis of a trinuclear Fe(II) complex, Fe₃TPM₂, supported by a 3-fold-sym. 2-pyridylpyrrolide ligand [i.e., tris(5-(pyridin-2-yl)-1H-pyrrol-2-yl)methane] that featured a rare cis-divacant octahedral (CDO) geometry at each Fe(II) center. Here, a series of truncated 2-pyridylpyrrolide ligands are described that support mono- and binuclear Fe(II) complexes that also exhibit CDO geometries. Metalation of the tetradentate ligand bis[5-(pyridin-2-yl)-1H-pyrrol-2-yl]methane (H₂BPM) in THF (THF) results in the binuclear complex Fe₂(BPM)₂(THF)₂ in which both Fe(II) ions are octahedrally coordinated. The coordinated THF solvent ligands are labile: THF dissociation leads to Fe₂(BPM)₂, which features five-coordinate Fe(II) ions. The Fe-Fe distance in these binuclear complexes can be elongated by ligand methylation. Metalation of bis[5-(6-methylpyridin-2-yl)-1H-pyrrol-2-yl]methane (H₂BPM^Me) in THF leads to the formation of four-coordinate, CDO Fe(II) centers in Fe(BPM^Me)₂. Further ligand truncation affords bidentate ligands 2-(1H-pyrrol-2-yl)pyridine (PyrPyrrH) and 2-methyl-6-(1H-pyrrol-2-yl)pyridine (Pyr^MePyrrH). Metalation of these ligands in THF affords six-coordinate complexes Fe(PyrPyrr)₂(THF)₂ and Fe(Pyr^MePyrr)₂(THF)₂. Dissociation of labile solvent ligands provides access to four-coordinate Fe(II) complexes. Ligand disproportionation at Fe(PyrPyrr)₂ results in the formation of Fe(PyrPyrr)₃ and Fe(0). Ligand methylation suppresses this disproportionation and enables isolation of Fe(Pyr^MePyrr)₂, which is rigorously CDO. Complete ligand truncation, by separating the 2-pyridylpyrrolide ligands into the constituent monodentate pyridyl and pyrrolide donors, affords Fe(Pyr)₂(Pyrr)₂ in which Fe(II) is tetrahedrally coordinated. Computational anal. indicates that the potential energy surface that dictates the coordination geometry in this family of four-coordinate complexes is fairly flat in the vicinity of CDO coordination. These synthetic studies provide the structural basis to explore the implications of CDO geometry on Fe-catalyzed reactions. Four-coordinate transition metal complexes can adopt a diverse array of coordination geometries, with square planar and tetrahedral coordination being the most prevalent. Previously, the authors reported the synthesis of a trinuclear Fe(II) complex, Fe3TPM2, supported by a three-fold sym. 2-pyridylpyrrolide ligand (i.e., tris(5-(pyridin-2-yl)-1H-pyrrol-2-yl)methane), that featured a rare cis-divacant octahedral (CDO) geometry at each Fe(II) center. Here, a series of truncated 2-pyridylpyrrolide ligands is described that support mono- and binuclear Fe(II) complexes that also exhibit CDO geometries. Metalation of tetradentate ligand bis(5-(pyridin-2-yl)-1H-pyrrol-2-yl)methane (H₂BPM) in THF results in a binuclear complex Fe₂(BPM)₂(THF)₂ in which both Fe(II) ions are octahedrally coordinated. The coordinated THF solvent ligands are labile: THF dissociation leads to Fe₂(BPM)₂, which features five-coordinate Fe(II) ions. The Fe-Fe distance in these binuclear complexes can be elongated by ligand methylation. Metalation of bis(5-(6-methylpyridin-2-yl)-1H-pyrrol-2-yl)methane (H₂BPMMe) in THF leads to the formation of four-coordinate, CDO Fe(II) centers in Fe(BPMMe)₂. Further ligand truncation affords bidentate ligands 2-(1H-pyrrol-2-yl)pyridine (PyrPyrrH) and 2-methyl-6-(1H-pyrrol-2-yl)pyridine (PyrMePyrrH). Metalation of these ligands in THF affords six-coordinate complexes Fe(PyrPyrr)₂(THF)₂ and Fe(PyrMePyrr)₂(THF)₂. Dissociation of labile solvent ligands provides access to four-coordinate Fe(II) complexes. Ligand disproportionation at Fe(PyrPyrr)₂ results in the formation of Fe(PyrPyrr)₃ and Fe(0). Ligand methylation suppresses this disproportionation and enables isolation of Fe(PyrMePyrr)₂, which is rigorously CDO. Complete ligand truncation, by separating the 2-pyridylpyrrolide ligands into the constituent monodentate pyridyl and pyrrolide donors, affords Fe(Pyr)₂(Pyrr)₂ in which the Fe(II) is tetrahedrally coordinated. Computational anal. indicates that the potential energy surface that dictates the coordination geometry in this family of four-coordinate complexes is fairly flat in the vicinity of CDO coordination. These synthetic studies provide the structural basis to explore the implications of CDO geometry on Fe-catalyzed reactions.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem