104704-09-8

Basic information

• Product Name: 4-Formyl-4'-methyl-2,2'-bipyridine
• Synonyms: 4-Formyl-4'-methyl-2,2'-bipyridine;[2,2'-Bipyridine]-4-carboxaldehyde,4'-methyl-;2-(4-methylpyridin-2-yl)pyridine-4-carbaldehyde
• CAS NO: 104704-09-8
• Molecular Formula: C₁₂H₁₀N₂O
• Molecular Weight: 198.22
• Mol File: 104704-09-8.mol
• Article Data: 63

Chemical Properties

• Melting Point: 130-131 °C
• Boiling Point: 368.7 °C at 760 mmHg
• Flash Point: 180.4 °C
• Appearance: /
• Density: 1.172 g/cm³
• PKA: 4.37±0.30(Predicted)
• CAS DataBase Reference: 4-Formyl-4'-methyl-2,2'-bipyridine(CAS DataBase Reference)
• NIST Chemistry Reference: 4-Formyl-4'-methyl-2,2'-bipyridine(104704-09-8)
• EPA Substance Registry System: 4-Formyl-4'-methyl-2,2'-bipyridine(104704-09-8)

Safety Data

• Hazardous Substances Data: 104704-09-8(Hazardous Substances Data)

Usage

General Description

4-Formyl-4'-methyl-2,2'-bipyridine is a chemical compound with the molecular formula C13H11N2O. It is a derivative of bipyridine, which is a heterocyclic compound and a common ligand in coordination chemistry. The compound features a formyl (aldehyde) group and a methyl group attached to the bipyridine ring system. This chemical is often used as a ligand in the synthesis of coordination complexes, where it can form strong coordination bonds with metal ions. It is also used in organic synthesis and can be found in various commercial products. Its properties and uses make it a valuable compound in the fields of chemistry and material science.

Upstream product

• 1134-35-6 4,4'-dimethyl-2,2'-bipyridines 
• 103946-54-9 4'-methyl-2,2'-bipyridine-4-carboxylic acid 
• 141-78-6 ethyl acetate 
• 56100-19-7 4-methyl-2,2'-bipyridine 
• 108-89-4 picoline 
• 81998-04-1 4-(hydroxymethyl)-4'-methyl-2,2'-bipyridine 
• 81998-03-0 4,4’-dimethyl-2,2’-bipyridine N-oxide 

Downstream Products

• 74173-48-1 4-vinyl-4'-methyl-2,2'-bipyridine 
• 6813-38-3 2,2'-Bipyridine-4,4'-dicarboxylic acid 
• 1621997-92-9 4-(N-(2-(N-(tert-butoxycarbonyl)amino)-5-methoxyphenyl)aminomethyl)-4'-methyl-2,2'-bipyridine 
• 1431295-08-7 C₁₃₆H₁₆₀N₃₀ 

Relevant articles and documents

A lysosome-targeted ruthenium(II) polypyridyl complex as photodynamic anticancer agent

Polypyridyl ruthenium complexes as novel photosensitizers had drawn attention due to its high selectivity towards cancer cells and low toxicity to normal cells. Herein, we synthesized a lysosome-targeted polypyridyl ruthenium complex Rhein-Ru(bpy)3 (bpy = 2,2′-bipyridine, rhein = 4,5-dihydroxy-9,10-dioxoanthracene-2-carboxylic acid), tethering with the Chinese medicine herb rhein. Rhein-Ru(bpy)3 exhibited high phototoxicity with short time of irradiation against tumor cell lines with the IC50 value of 2.4– 8.7 μM, and higher cytotoxicity against cisplatin-resistant A2780 cell lines, suggesting that Rhein-Ru(bpy)3 could overcome the cisplatin resistance. Moreover, Rhein-Ru(bpy)3 displayed low cytotoxicity towards cell lines in dark incubation, which was beneficial to reduce the toxic side effects towards normal cell lines. Besides, the confocal imaging and western blotting assay results suggested that Rhein-Ru(bpy)3 could induce cancer cell death through the autophagy pathway. These results inspired us that lysosome-targeted photosensitizers based on ruthenium complexes showed great potential for photodynamic therapy (PDT) application in cancer treatment.

Multinuclear ruthenium(II) complexes as anticancer agents

A series of dinuclear ruthenium(ii) complexes that contain labile chlorido ligands, [{Ru(tpy)Cl}2{μ-bbn}]2+ {designated Cl-Rubbn; tpy = 2,2′:6′,2′′-terpyridine, bbn = bis[4(4′-methyl-2,2′-bipyridyl)]-1,n-alkane (n = 7, 10, 12, 14 or 16)} and derivatives containing nitro substituents on the tpy ligand and/or secondary amines within the bbn linking chain have been synthesised and their potential as anticancer agents examined. Some of the Cl-Rubbn species showed good anticancer activity against MCF-7 and MDA-MB-231 breast cancer cell lines, with the Cl-Rubb12 complex being four-times more active than cisplatin. Inclusion of nitro substituents on the tpy ligands of Cl-Rubb12 resulted in significantly decreased anticancer activity. The incorporation of amine groups into the linking ligand did not increase the anticancer activity of the Cl-Rubbn complexes. The Cl-Rubbn complexes and those containing amine groups in the linking chain aquated at approximately the same rate, with 50% aquation within 120 minutes. By comparison, the complexes containing nitro substituents on the tpy ligand aquated extremely slowly, with 60% of the chlorido complex remaining 24 hours after they were dissolved in water. Cyclic voltammetry with the model mononuclear complex [Ru{(NO2)3tpy}(Me2bpy)Cl] + {(NO2)3tpy = 4,4′,4′′- trinitro-2,2′:6′,2′′-terpyridine} showed that the nitro substituents exerted a strong effect on the ruthenium centre, with the anodic peak corresponding to the Ru(iii/ii) couple shifted positively by 300 mV compared to that from the non-nitrated parent complex [Ru(tpy)(Me 2bpy)Cl]+. 1H NMR studies of the reaction of the Cl-Rubbn complexes with GMP indicated that the ruthenium complexes covalently bound the nucleotide slowly, with 33% bound in 24 hours. However, the results of this study suggest that the cytotoxicity of the dinuclear ruthenium complexes is a combination of covalent and reversible binding with DNA. the Partner Organisations 2014.

Molecular recognition and reactivity of ruthenium(II) bipyridine barbituric acid guests in the presence of complementary hosts: Ruthenium(II) promoted enolization of barbituric acids in guest-host complexes

The binding of the host H1 (N,N'-bis(6-pivalamidopyrid-2-yl)-3,5- pyridinedicarboxamide) to three different ruthenium polypyridine complexes with an attached barbituric acid and barbital moieties (RuG1, RuG2, RuG3) (where G1 = 5-[4-(4'-methyl)-2,2'-bipyridylidene]-2,4,6-(1H,3H,5H)- pyrimidinetrione, G2 = 5-[4-(4'-methyl)-2,2'-bipyridyl]methyl-2,4,6- (1H,3H,5H)-pyrimidinetrione, and G3 = 5-ethyl, 5-[4-(4'-methyl)-2,2'- bipyridyl]methyl-2,4,6-(1H,3H,5H)-pyrimidinetrione) and Ru = (4,4'-di-tert- butyl-bpy)2Ru (bpy = 2,2'-bipyridine) has been studied in chlorinated solvents by NMR and fluorescence titrations. Significant binding was only observed between H1 and the RuG2 series, while steric hindrance significantly diminished binding between H1 and RuG1 or RUG3. The high binding constant for RuG2 was related to the presence of the enolate form of the barbituric acid guest which forms strong H-bonds with the complementary host H1. For the organic barbituric acid and barbital guests, the keto and enol bind only weakly to H1 (K ~ 102 M-1); binding is further increased in the presence of base to generate the enolate. In contrast, formation of the RuG2 enolate occurs upon binding to H1 without any additional base. The ruthenium polypyridine cation (compared to the organic barbituric acid derivatives) facilitates ionization of the enol to enolate thus producing a better complementary H-bonding site between the guest and host. Molecular mechanics calculations confirmed the experimental observations that the enolate has the highest binding constant to the Host H1, while the corresponding enol form has the weakest binding.

Atom transfer radical polymerization preparation and photophysical properties of polypyridylruthenium derivatized polystyrenes

A ruthenium containing polymer featuring a short carbonyl-amino-methylene linker has been prepared by atom transfer radical polymerization (ATRP). The polymer was derived from ATRP of the N-hydroxysuccinimide (NHS) derivative of p-vinylbenzoic acid, followed by an amide coupling reaction of the NHS-polystyrene with Ru(II) complexes derivatized with aminomethyl groups (i.e., [Ru(bpy)2(CH3-bpy-CH2NH2)] 2+ where bpy is 2,2′-bipyridine, and CH3-bpy-CH 2NH2 is 4-methyl-4′-aminomethyl-2,2′- bipyridine). The Ru-functionalized polymer structure was confirmed by using nuclear magnetic resonance and infrared spectroscopy, and the results suggest that a high loading ratio of polypyridylruthenium chromophores on the polystyrene backbone was achieved. The photophysical properties of the polymer were characterized in solution and in rigid ethylene glycol glasses. In solution, emission quantum yield and lifetime studies reveal that the polymer's metal-to-ligand charge transfer (MLCT) excited states are quenched relative to a model Ru complex chromophore. In rigid media, the MLCT-ground state band gap and lifetime are both increased relative to solution with time-resolved emission measurements revealing fast energy transfer hopping within the polymer. Molecular dynamics studies of the polymer synthesized here as well as similar model systems with various spatial arrangements of the pendant Ru complex chromophores suggest that the carbonyl-amino-methylene linker probed in our target polymer provides shorter Ru-Ru nearest-neighbor distances leading to an increased Ru*-Ru energy hopping rate, compared to those with longer linkers in counterpart polymers.

Telechelic poly(ε-caprolactones) with tethered mixed ligand ruthenium(II) chromophores

Well-characterized templates of polymer-forming ligands and their ruthenium tris(αα′-diimine) initiators were utilized to divergently ring open an ε-caprolactone monomer. The same polymers were also obtained through the synthesis of quinoline and bipyridine diimine ligands incorporating poly(ε-caprolactone) (PCL) chains. These polymers contain vacant molecular recognition sites, enabling subsequent chelation of these macroligands to metal precursors. Both methods provided telechelic (ε-caprolactone) ruthenium(II)-centered polyesters of various hierarchy. Solution properties and thermal behaviour of such polyesters are described.

Highly efficient and selective photocatalytic oxidation of sulfide by a chromophore-catalyst dyad of ruthenium-based complexes

Electronic coupling across a bridging ligand between a chromophore and a catalyst center has an important influence on biological and synthetic photocatalytic processes. Structural and associated electronic modifications of ligands may improve the efficiency of photocatalytic transformations of organic substrates. Two ruthenium-based supramolecular assemblies based on a chromophore-catalyst dyad containing a Ru-aqua complex and its chloro form as the catalytic components were synthesized and structurally characterized, and their spectroscopic and electrochemical properties were investigated. Under visible light irradiation and in the presence of [Co(NH3)5Cl]Cl2 as a sacrificial electron acceptor, both complexes exhibited good photocatalytic activity toward oxidation of sulfide into the corresponding sulfoxide with high efficiency and >99% product selectivity in neutral aqueous solution. The Ru-aqua complex assembly was more efficient than the chloro complex. Isotopic labeling experiments using 18O-labeled water demonstrated the oxygen atom transfer from the water to the organic substrate, likely through the formation of an active intermediate, Ru(IV)=O.

Synthesis and Luminescence Properties of Di- and Tri-methylene Linked Tris(2,2'-bipyridine)ruthenium(II) Complex Dimers. Ground-Excited State Interaction

Di- and tri-methylene-linked Ru(bpy)3(2+) complexes 2 were synthesized.The luminescence properties of 2 were compared with those of its component monomer.In the excited 2 systems, the intermolecular interaction leading to the enhanced quenching or the formation of a new triplet excimer was not observed.

Bipyridine carbaldehydes as electrophiles in the Morita-Baylis-Hillman reaction: synthesis of highly functionalized bipyridyl ligands and a macrocycle

A simple and efficient Morita-Baylis-Hillman (MBH) reaction of bipyridine carbaldehydes and unexplored activated alkenes afforded highly functionalized bipyridyl ligands. Particularly, one-pot MBH reaction of 2,2′-bipyridine-4,4′-dicarbaldehyde and 2,2′-bipyridine-4-methyl-4′-carbaldehyde with 1,6-hexanediol diacrylate afforded a twenty membered bipyridyl macrocycle and bis MBH adducts, respectively. Synthetic transformations of mono and bis MBH adducts thus obtained have been demonstrated by preparing bipyridyl N-oxide and [3+2]-cycloadduct of azomethine ylide derived from isatin and proline.

Synthesis, photophysical properties and spectroelectrochemical characterization of 10-(4-methyl-bipyridyl)-5,15-(pentafluorophenyl)corrole

The new bipyridyl-corrole dye 10-(4-methyl-bipyridyl)-5,15-(pentafluorophenyl)corrole, encompassing a coordenative methyl-bipyridine moiety (corrole 2), was prepared starting from 5-(pentafluorophenyl)dipyrromethane and reacting it with methyl-bipyridyl-carboxaldehyde by Grykós methodology. It was further characterized by spectroscopic and electrochemical methods. In addition, we investigated experimental photophysical properties, photostability, reactive oxygen species generation (ROS) and aggregation phenomena, which are relevant when selecting photosensitizers used in photodynamic therapy and many other applications. Photophysical properties have demonstrated that the corrole 2 dissolved in dichloromethane has a triplet quantum yield formation of about 51%. Fluorescence and internal conversion quantum yields of 4% and 45%, respectively, have also been determined in order to evaluate which could be was the main pathway of the excited state relaxation. Triplet state formation was also confirmed by measuring indirectly 1O2 generation. Additionally, quantum chemistry calculations indicated that the most probable intersystem-crossing pathway takes place through S1-T1, corroborating our rate equation model.

Electron transfer from photoexcited naphthalene-1,4:5,8-bis(dicarboximide) radical anion to Mn(bpy)(CO)3X and Re(bpy)(CO)3X CO2 reduction catalysts linked via a saturated methylene bridge

Supramolecular systems that connect a naphthalene-1,4:5,8-bis(dicarboximide) (NDI) radical anion donor to Mn(bpy)(CO)3Br or Re(bpy)(CO)3Cl CO2 reduction catalysts via a methylene bridge have been synthesized and studied by femtosecond transient visible, near-infrared and mid-infrared spectroscopy. The use of the methylene bridge to link NDI to the complexes does not affect the reduction potentials of the metal complexes. Selective photoexcitation of NDI?? to 2*NDI?? results in ultrafast reduction of the bipyridine (bpy) ligands on both the Mn and Re complexes to form Mn(I)(bpy??)(CO)3X and Re(I)(bpy??)(CO)3X in near unity quantum yield, respectively. The initial formation of Mn(I)(bpy??)(CO)3X is unexpected based on previous electrochemical data that indicates the Mn(I) center is reduced at a more positive potential than the bpy ligand. Moreover, the rate of forward electron transfer in the Mn complex was found to be faster than in the Re complex, while the rate of the back electron transfer in the Re complex was faster than in the Mn complex.

Bioorthogonal oxime ligation of a Mo(CO)4(N-N) CO-releasing molecule (CORM) to a TGF β-binding peptide

Carbon monoxide is now well-established as an endogenously produced gasotransmitter in humans. To utilizes its spectrum of biological activity for therapeutic purposes, solid storage forms such as metal carbonyl complexes have to be used for easy handling and targeted delivery to the body. Thus, in the present work, a [Mo(CO)4(bpyCH3,CHO)] complex with an aldehyde group in a peripheral position on the 2,2′-bipyridine (bpy) ligand was coupled to a bioactive transforming growth factor (TGF) β-targeting peptide N-terminally functionalized with aminoxy acetic acid using the bioorthogonal and catalyst-free oxime ligation. CO release studies with the myoglobin assay as well as UV/Vis and IR spectroscopy showed the molybdenum tetracarbonyl moiety to slowly liberate carbon monoxide upon incubation in buffer in the dark. In addition, photoactivation at 468 nm with a LED array resulted in a significantly accelerated release of carbon monoxide, thus establishing this peptide bioconjugate as a new photoactivatable CO-releasing molecule (PhotoCORM) with a red-shifted excitation wavelength for better tissue penetration.

Iron(iii)-bipyridine incorporated metal-organic frameworks for photocatalytic reduction of CO2with improved performance

Metal-organic frameworks (MOFs) represent an emerging class of platforms to assemble single site photocatalysts for artificial photosynthesis. In this work, we report a new CO2 reduction photocatalyst (UiO-68-Fe-bpy) based on a robust Zr(iv)-MOF platform with incorporated Fe(bpy)Cl3 (bpy refers to the 4′-methyl-[2,2′-bipyridine] moiety) via amine-aldehyde condensation. We show that this hybrid catalyst can reduce CO2 to form CO under visible light illumination with excellent selectivity and enhanced activity with respect to its parent MOF and corresponding homogeneous counterpart. Using steady state and transient absorption (TA) spectroscopy, we show that the enhanced photocatalytic activity of UiO-68-Fe-bpy is attributed to the elongated excited state lifetime of Fe(bpy)Cl3 after being incorporated to the UiO-68-NH2 platform. This work demonstrates the great potential of MOFs as a next generation platform for solar fuel conversion.

A2B corrole with a meso-[PtII(bipy)Cl2]-substituent: Synthesis, electronic structure and highly efficient electrocatalyzed hydrogen evolutions

Synthesis and electronic structure of meso-2,2′-bipyridine substituted H3corrole and its Pt(II) complex were described. This study demonstrates that A2B type corrole contianing meso-[PtII(bipy)Cl2] substituents are highly efficient catalysts for hydrogen evolutions with low overpotential (50 mV vs RHE), low Tafel slope (59 mV/dec) and robust catalytic behaviors. The efficient catalytic properties can be readily enhanced by charge transfer between bridging conjugated aromatic ring (corrole) and meso-[PtII(bipy)Cl2] catalytic center.

Phosphonate-Mediated Immobilization of Rhodium/Bipyridine Hydrogenation Catalysts

RhL2 complexes of phosphonate-derivatized 2,2′-bipyridine (bpy) ligands L were immobilized on titanium oxide particles generated in situ. Depending on the structure of the bipy ligand—number of tethers (1 or 2) to which the phosphonate end groups are attached and their location on the 2,2′-bipyridine backbone (4,4′-, 5,5′-, or 6,6′-positions)—the resulting supported catalysts showed comparable chemoselectivity but different kinetics for the hydrogenation of 6-methyl-5-hepten-2-one under hydrogen pressure. Characterization of the six supported catalysts suggested that the intrinsic geometry of each of the phosphonate-derivatized 2,2′-bipyridines leads to supported catalysts with different microstructures and different arrangements of the RhL2 species at the surface of the solid, which thereby affect their reactivity.

Novel Ru(II)/Os(II)-Exchange Homo- and Heterometallic Polypyridyl Complexes with Effective Energy Transfer

Two novel homometallic Ru?Ru and heterometallic Ru?Os dimers and trimers, [MII(bpy)2(4-tpy-4′-methyl-2,2′-bipyridine)MII(tpy)]4+ and [MII(bpy)2](4-tpy-4′-tpy-2,2′-bipyridine)(MII(tpy))2]6+, have been first prepared and characterized. Electrochemical properties of the metal-based reversible oxidation and ligand-based reduction are measured. Spectroscopic analysis of these complexes exhibits for every Ru- or Os-based subunit an individual intense absorption spectrum extended over the entire UV and visible region. The heteronuclear complexes [RuII(bpy)2(4-tpy-4′-methyl-2,2′-bipyridine)OsII(tpy)]4+, [RuII(bpy)2](4-tpy-4′-tpy-2,2′-bipyridine)(OsII(tpy))2]6+, and [OsII(bpy)2](4-tpy-4′-tpy-2,2′-bipyridine)(RuII(tpy))2]6+ display a weak emission spectrum in the near-infrared region (NIR). The luminescence of the polynuclear assemblies is quantitatively quenched, by intramolecular energy transfer to the lower-lying metal-to-ligand charge transfer (3MLCT) and metal-centered (3MC) state of the Os(II)-based center or Ru(II)-terpyridine moiety at room temperature.

Influence of PNIPAm on log Kf of a copolymerized 2,2′-bipyridine: Revised bifunctional ligand design for ratiometric metal-ion sensing

Here we describe the synthesis of a model compound (1) based upon a previously reported bifunctional 2,2′-bipyridine (2). Ligand pKa and thermodynamic stability constants were investigated by potentiometric titrations for 1 in order to assess the metal-binding capabilities of 2 following subsequent incorporation within a temperature-responsive polymer that functions as a fluorescent metal-ion indicator. While the logKCu1 measured here was found to be 8.86 ± 0.05 at 25 °C, this value was previously seen to fall 2.8 orders of magnitude following copolymerization of 2 with poly(N-isopropylacrylamide) (PNIPAm). This drop in affinity was attributed to stabilization of the neutral ligand by the polymer environment and elevated temperatures at which metal-binding experiments were performed. ΔH (-54.4 kJ mol-1) and ΔS (-12.8 J K-1 mol-1) were therefore determined through variable temperature titrations in order to establish the temperature dependence of logKCu1. Doing so enabled elucidation of the overall effect that the polymer environment exerts on thermodynamic stability of copolymerized 2. Specifically, the polymer indicator was found to decrease the thermodynamic stability by 2.2 orders of magnitude, whereas elevated temperatures account for the additional 0.6 order of magnitude drop observed. This finding has implications regarding the design of future bifunctional ligands for ratiometric sensing within our temperature-responsive polymer indicator.

Synthesis, characterization and photophysical properties of a new Cu2+ selective phosphorescent sensor

A new Cu(II) selective phosphorescent sensor based on a cationic iridium(III) complex was synthesized and characterized. Compared with other commonly coexisting metal ions, the Ir(III) complex displayed significant phosphorescence quenching for detecting Cu2+ with a 1:1 stoichiometry in MeOH/H2O (1:1, v/v) solution. Upon addition of Cu2+, the rapid quenching of emission intensity provided a sensitive method for detection of Cu2+. The corresponding detection limit was determined to be 7.6 × 10?8 M and the association constant between the Ir(III) complex and Cu2+ was calculated to be 0.31 × 105 M?1. Luminescence imaging experiments demonstrated that this Ir(III) complex was cell permeable and suitable for monitoring intracellular Cu2+ in living Hela cells by confocal microscopy.

Polynuclear heteroleptic ruthenium(II) photoredox catalysts: Evaluation in blue-light-mediated, regioselective thiol-ene reactions

Polynuclear heteroleptic ruthenium(II) photosensitisers combining either imine or amine-functionalised bipyridyl ligands were synthesised (via Schiff-base condensation/reductive amination reactions), characterised and investigated for their photoreactivity in the hydrothiolation reaction. Furthermore, electrochemical, electronic absorption and emission studies of the complexes were conducted. All the ligand-modified, heteroleptic complexes show red-shifted emission spectra (614–633 nm) relative to the canonical [Ru(bpy)3](PF6)2 complex (609 nm), attributed to the transition from the triplet MLCT excited state (3MLCT) to the ground state. The complexes were evaluated as visible-light photoredox catalysts in the radical hydrothiolation reaction of olefins (thiol-ene coupling) to afford thioethers. Control reactions performed in the absence of the photocatalyst resulted in either significantly lower yields (6%) or no product formation, demonstrating the role of the complexes as photoredox catalysts. The reactions carried out using trinuclear complexes (Ered (Ru2+*/+) = +0.300 V vs Ag/Ag+) resulted in increased yields in comparison with their respective mononuclear congeners and greater than those reported for [Ru(bpy)3](PF6)2, demonstrating the benefits of using polynuclear photocatalysts for photoinitiated redox catalysis reactions.