Category: 948552-36-1

Application In Synthesis of 1H-Pyrazole-5-carbaldehyde. The reaction of aromatic heterocyclic molecules with protons is called protonation. Aromatic heterocycles are more basic than benzene due to the participation of heteroatoms. Compound: 1H-Pyrazole-5-carbaldehyde, is researched, Molecular C4H4N2O, CAS is 948552-36-1, about Mononuclear complexes of FeII, CoII and CoIII containing imine-based ligands of 8-aminoquinoline and 7-aminoindazole: spin state tuning of FeII complexes in solution. Author is Sanchez-Viveros, Jose Manuel; Bucio-Ortega, Job; Ortiz-Pastrana, Naytze; Olguin, Juan.

Five mononuclear metal complexes were synthesized, three complexes of iron(II), one complex of cobalt(III) and one complex of cobalt(II) containing imine ligands based on 8-aminoquinoline or 7-aminoindazole and 2-formylpyridine or 3-formylpyrazole, namely [FeII(L1)2](BF4)2 (1), [CoIII(L1)(L1′)](BF4)2 (2), [FeII(HL2)2](BF4)2 (3), [FeII(HL3)2](BF4)2 (4) and [CoII(HL3)2](BF4)2 (5). Iron(II) complexes 1 and 3 derived from 8-aminoquinoline and 2-formylpyridine or 3-formylpyrazole, resp., were stabilized in the LS-state (S = 0) as proven by NMR spectroscopy and x-ray crystallog., whereas complex 4, based on indazole and pyridine, shows a gradual and incomplete spin conversion in CD3CN solution (the Evans method). According to NMR spectroscopy and x-ray crystallog., the cobalt complexes 2 and 5 were stabilized in different oxidation states.

The article 《Mononuclear complexes of FeII, CoII and CoIII containing imine-based ligands of 8-aminoquinoline and 7-aminoindazole: spin state tuning of FeII complexes in solution》 also mentions many details about this compound(948552-36-1)Application In Synthesis of 1H-Pyrazole-5-carbaldehyde, you can pay attention to it, because details determine success or failure

Reference:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Epoxy compounds usually have stronger nucleophilic ability, because the alkyl group on the oxygen atom makes the bond angle smaller, which makes the lone pair of electrons react more dissimilarly with the electron-deficient system. Compound: 1H-Pyrazole-5-carbaldehyde, is researched, Molecular C4H4N2O, CAS is 948552-36-1, about Improving iodine adsorption performance of porous organic polymers by rational decoration with nitrogen heterocycle.Formula: C4H4N2O.

Four kinds of porous aminal-linked organic polymers (PAOPs) were synthesized via one-step condensation between cheap melamine and resp. aldehydes decorated with different nitrogen heterocycle, to evaluate the influence of nitrogen heterocycle on the adsorption performance of target polymer toward iodine. Though having the smallest surface area of 209.9 m2/g, PAOP-4 decorated with pyridine group exhibits an adsorption capacity of 108 wt% (iodine/adsorbent weight%), surpassing other three PAOPs with Brunauer-Emmett-Teller area varying from 305.8 to 533.0 m2/g. Based on Raman spectral analyses, the characteristic band of I3- and I5- was used to evaluate the electronic interaction between iodine and the nitrogen heterocycle, giving an order of pyridine > tetrazole > pyrazole > imidazole. This manifests the vital role of chem. interaction playing in the iodine adsorption by PAOP-4, which is much helpful for designing high-performance organic adsorbent toward iodine.

After consulting a lot of data, we found that this compound(948552-36-1)Formula: C4H4N2O can be used in many types of reactions. And in most cases, this compound has more advantages.

Reference:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Szorcsik, Attila; Matyuska, Ferenc; Benyei, Attila; Nagy, Nora V.; Szilagyi, Robert K.; Gajda, Tamas published an article about the compound: 1H-Pyrazole-5-carbaldehyde( cas:948552-36-1,SMILESS:O=CC1=CC=NN1 ).Reference of 1H-Pyrazole-5-carbaldehyde. Aromatic heterocyclic compounds can be classified according to the number of heteroatoms or the size of the ring. The authors also want to convey more information about this compound (cas:948552-36-1) through the article.

Copper(II) complexes of a polydentate tripodal ligand L × 3HCl (L = N,N’,N”-tris(5-pyrazolylmethyl)-cis,cis-1,3,5-triaminocyclohexane) were characterized in both solution and solid states. Combined evaluation of potentiometric, UV-visible, and EPR data indicated the formation of two mononuclear (CuHL, CuL) and three trinuclear (Cu3H-xL2, x = 2, 3, 4) complexes. The high stability and spectroscopic properties of the CuL species indicate a coordination of two pyrazole rings in addition to the three secondary amino groups of L in a square pyramidal geometry. In parallel with the formation of trinuclear species, intense charge transfer bands appear at ∼400-500 nm, which indicate the formation of pyrazolate-bridged complexes. The crystal structure of [Cu3H-4L2](ClO4)2·5H2O (1) reveals the formation of a unique trinuclear complex that features a tetra(pyrazolate)-bridged linear tricopper(II) core. The Cu···Cu interat. distances are ∼3.8 Å. The two peripheral copper(II) ions have a slightly distorted square pyramidal geometry. The four pyrazole rings bound to the peripheral copper(II) ions are deprotonated and create a flattened tetrahedral environment for the central copper(II), i.e. the formation of the trinuclear complexes is under the allosteric control of the two peripheral copper(II) ions. The triply deprotonated trinuclear complex is an efficient catechol oxidase mimic with a surprisingly low pH optimum at pH = 5.6. Since the mononuclear CuL species is not able to promote the oxidation of 3,5-di-tert-butylcatechol, the authors assume that the central copper(II) ion of the trinuclear complex with an unsaturated coordination sphere has a fundamental role in the binding and oxidation of the substrate. The exptl. and structural details were further elaborated by a series of hybrid d. functional theory calculations that support the presence of an antiferromagnetically coupled ground state. However, the magnitude and the pattern of spin coupling are dependent on the composition of the functionals. The optimized theor. structures highlight the role of the crystal packing effects in inducing asymmetry between the two peripheral copper(II) sites.

After consulting a lot of data, we found that this compound(948552-36-1)Reference of 1H-Pyrazole-5-carbaldehyde can be used in many types of reactions. And in most cases, this compound has more advantages.

Reference:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

The reaction of an aromatic heterocycle with a proton is called a protonation. One of articles about this theory is 《Syntheses in the heterocyclic series. IV. Syntheses of heterocyclic aldehydes. 4-Pyrimidinecarboxaldehyde》. Authors are Bredereck, Hellmut; Sell, Ruediger; Effenberger, Franz.The article about the compound:1H-Pyrazole-5-carbaldehydecas:948552-36-1,SMILESS:O=CC1=CC=NN1).Safety of 1H-Pyrazole-5-carbaldehyde. Through the article, more information about this compound (cas:948552-36-1) is conveyed.

cf. CA 59, 10054b. A series of heterocyclic aldehyde acetals and aldehydes was prepared from the appropriate bifunctional compounds with an aldehyde acetal group. Me2NCH:CHCOCH(OEt)2 (I) and HN:CHNH2.AcOH (II) yielded 4-pyrimidinecarboxaldehyde di-Et acetal (III) and from this the free 4-pyrimidinecarboxaldehyde (IV). AcCH2COCH(OEt)2 (V), b10 101-3°, b0.001 48-50°, was prepared in 65% yield by the method of Panizzi (CA 38, 35003). AcCH(OAc)CH(OMe)2 (8.0 g.), b10 98-104°, in 50 cc. absolute MeOH refluxed 45 min. with 2 cc. 2% NaOMeMeOH yielded 5.0 g. AcCH(OH)CH(OMe)2 (VI), b8 87°, n20D 1.4302. AcCH(OMe)2 (29.2 g.) and 29.4 g. Me2NCH(OEt)2 heated 20 h. at 80° gave 32 g. I, b0.001 115-20°, n20D 1.5210, m. 25-30°. N2H4.H2SO4 (16.3 g.) in 100 cc. 10% aqueous NaOH treated dropwise at ∼15° with stirring with 23.5 g. V and the mixture stirred 1 h. at 15° yielded 20.5 g. (crude) 5(3)-methylpyrazole-3(5)-carboxaldehyde di-Et acetal (VII), b0.001 94-6°, n20D 1.4744. VII (4.0 g.), 0.85 cc. concentrated HCl, and 31 cc. H2O kept 10 h. at room temperature yielded 2.25 g. 5(3)-methylpyrazole-3(5)-carboxaldehyde (VIII), m. 188-9° (decomposition); oxime m. 171° (H2O); semicarbazone m. 193-8° (decomposition) (H2O); phenylhydrazone m. 184° (50% aqueous EtOH). VIII (0.5 g.) in 50 cc. concentrated NH4OH yielded during 3 days 0.4 g. 3(5)-methyl-5(3)-aminomethylenepyrazole, decomposed 170-3°. VIII (1.1 g.) and 2 cc. dry piperidine heated 3 h. at 80-90° gave 1.15 g. 3(5)-methyl-5(3)-piperidinomethylenepyrazole, m. 228-9° (decomposition). VIII (0.5 g.) in 30 cc. N2H4.H2O kept 3 days gave 0.3 g. 5(3)-methylpyrazole-3(5)-aldehyde azine, pale yellow. N2H4.H2SO4 (6.5 g.) in 40 cc. 10% aqueous NaOH treated dropwise with stirring at room temperature with 10 g. I, and the mixture stirred 2 h. and kept overnight gave 7.1 g. pyrazole-3-carboxaldehyde di-Et acetal (IX), b0.001 86°, n20D 1.4746; phenylhydrazone m. 199-201°. IX (4.0 g.) in 1% HCl kept several hrs. at room temperature gave 1.8 g. pyrazole-3-carboxaldehyde, m. 146-7° (H2O). HN:C(NH2)2 carbonate (3.1 g.) in 1 cc. concentrated H2SO4 and 5 cc. H2O treated with 5.67 g. Ba(OH)2 in 50 cc. H2O, the mixture filtered, concentrated to 10 cc., and treated 3 days with 5.0 g. VI, and the crude product (5.5 g.) treated in MeOH with picric acid in MeOH gave 5.5 g. (crude) picrate of 2-amino-4(5)-methylimidazole-5(4)-carboxaldehyde di-Me acetal (X), m. 229-30° (MeOH). VI (7.4 g.), 6.3 g. MeSC(:NH)NH2.HCl (XI.HCl), and 25 cc. absolute EtOH treated during 1 h. at room temperature with 1.15 g. Na in 25 cc. absolute EtOH, kept 3 days, and the oily product (2.0 g.) treated with saturated picric acid in MeOH gave 0.1 g. picrate, decomposed 163-5°, of the 2-MeS analog of X. VI (7.4 g.) and 7.8g. PhC(:NH)NH2.HCl gave 3.7 g. (crude) 2-Ph analog of X, m. 144-5° (AcOBu); picrate m. 239-40° (decomposition) (MeOH). V (75.2 g.), 72.4 g. XI, and 160 cc. H2O treated dropwise with stirring at room temperature during 0.5 h. with 29.2 g. KOH in 40 cc. H2O gave 49 g. di-Et acetal (XII) of 2-methylthio-6-methyl-4-pyrimidinecarboxaldehyde (XIII), yellowish oil, b0.001, 100-3°, n20D 1.5229; oxime m. 218-19° (decomposition)(EtOH); semicarbazone, light yellow, m. 215-20° (EtOH); phenylhydrazone, yellow, m. 182° (EtOH). XII (10.0 g.), 100 cc. 50% EtOH, and 1 cc. concentrated HCl refluxed 1 h. gave 5.7 g. XIII, m. 87° (petr. ether), b0.001 93-7°. XII (22.4 g.) in 400 cc. EtOH refluxed 2 h. with ∼100 g. Raney Ni gave 11.8 g. di-Et acetal (XIV) of 6-methylpyrimidine-4-carboxaldehyde (XV), b0.001 61-5°, n20D 1.4655; oxime m. 150° (H2O); semicarbazone m. 217° (EtOH); phenylhydrazone, yellow, m. 120-1° (50% EtOH). XIV (50 g.) in 50 cc. 50% EtOH and 0.5 cc. concentrated HCl refluxed 1 h. gave 3.4 g. XV, m. 53° (petr. ether). V (19 g.), 18.8 g. MeC(:NH)NH2.HCl, and 42 g. K2CO2 in 150 cc. H2O kept 3 days yielded 9.9 g. 2,6-dimethylpyrimidine-4-carboxaldehyde di-Et acetal (XVI), b0.001 50-9°, n20D 1.4712-1.4737; oxime m. 213° (1:3 EtOH-H2O). I (15 g.) and 15.6 g. PhC(:NH)NH2.HCl in 40 cc. H2O treated dropwise with stirring at 30° with 5.6 g. KOH in 20 cc. H2O and kept 2 days yielded 5.0 g. 2-Ph analog of XVI, viscous, yellow oil, b0.001 110-19°; oxime m. 165-6°(50% EtOH). I (20.5 g.), 18.3 g. XI, and 60 cc. H2O treated dropwise during 0.5 h. at room temperature with 7.3 g. KOH in 25 cc. H2O, stirred 1 h. at 50°, and kept several days yielded 14.3 g. pale yellow di-Et acetal (XVII) of 2-methylthiopyrimidine-4-carboxaldehyde (XVIII), b0.001, 112-16°, n20D 1.5190; oxime m. 165° (50% EtOH); semicarbazone, yellowish, m. 224° (50% EtOH); phenylhydrazone, yellow, m. 192-4° (EtOH). XVII (6.0 g.) in 60 cc. 50% EtOH refluxed 40 min. with 0.9 cc. concentrated HCl gave 2.8 g. XVIII, m. 68° (petr. ether), b0.001 110-12°. I (31.2 g.) and 40.2 g. II heated 2.5 h. at 115° gave 27 g. III, b0.001 63-5°, n20D 1.4683. XVII (20 g.) in 400 cc. EtOH refluxed 2 h. with ∼90 g. Raney Ni gave 5.7 g. III, b0.001 65-7°, n20D 1.4683. III gave in air III.H2O, m. 93° (sublimed at 70-80°/8 mm.); oxime m. 153-4°; semicarbazone m. 212° (decomposition); phenylhydrazone, yellow, m. 168-9° (50% EtOH). I (15 g.), 10.8 g. MeC(:NH)NH2.HCl, and 20 cc. absolute EtOH treated with stirring at 40° with 2.6 g. Na in 40 cc. EtOH, and the mixture stirred 2 h. at 40° and refluxed 15 min. gave 10.8 g. 2-Me derivative (XIX) of III, b7 104°, n20D 1.4719, phenylhydrazone m. 172° (50% EtOH). XIX (5.8 g.), 80 cc. H2O, and 0.35 cc. concentrated H2SO4 heated 3 h. at 60° and 1 h. at 70° yielded 5.5 g. 2-Me derivative of IV.H2O, m. 66° (sublimed in vacuo at 30°). PhC(:NH)NH2.HCl (15.5 g.), 20 g. I, and 20 cc. absolute EtOH treated dropwise at room temperature with 2.3 g. Na in 60 cc. absolute EtOH, and the mixture stirred 1 h. and kept overnight gave 15.7 g. 2-Ph derivative (XX) of III, b0.002 123°, n20D 1.5506; oxime m. 138°; phenylhydrazone m. 211° (EtOH). XX (5.2 g.), 30 cc. 50% EtOH, and 0.45 g. concentrated HCl refluxed 40 min. yielded 1.2 g. 2-Ph derivative of IV, m. 118° (cyclohexane). I (8.6 g.), 2.6 g. urea, and 0.99 g. Na in 40 cc. absolute EtOH refluxed 6 h. gave 1.4 g. 2-OH derivative of III, m. 143-4° (EtOH). HN:C(NH2)2 carbonate (1.12 g.) in the min. amount 1:5 H2SO4-H2O, treated with aqueous Ba(OH)2, filtered, concentrated to 10 cc., and treated 24 h. with 2.5 g. I yielded 0.80 g. 2-NH2 derivative of III, m. 137-8° (EtOH). IV (1.0 g.) in 5 cc. absolute EtOH treated with a few drops aqueous KCN yielded 0.60 g. pyrimidoin, orange-yellow, decomposed ∼239° (1:1 EtOH-Me2SO).

After consulting a lot of data, we found that this compound(948552-36-1)Safety of 1H-Pyrazole-5-carbaldehyde can be used in many types of reactions. And in most cases, this compound has more advantages.

Reference:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

The preparation of ester heterocycles mostly uses heteroatoms as nucleophilic sites, which are achieved by intramolecular substitution or addition reactions. Compound: 1H-Pyrazole-5-carbaldehyde( cas:948552-36-1 ) is researched.Safety of 1H-Pyrazole-5-carbaldehyde.Matyuska, Ferenc; May, Nora V.; Benyei, Attila; Gajda, Tamas published the article 《Control of structure, stability and catechol oxidase activity of copper(II) complexes by the denticity of tripodal platforms》 about this compound( cas:948552-36-1 ) in New Journal of Chemistry. Keywords: copper pyrazolylmethylaminoethylamine complex preparation ESR formation constant; crystal structure copper pyrazolylmethylaminoethylamine. Let’s learn more about this compound (cas:948552-36-1).

Copper(II) complexes of a new polydentate tripodal ligand trenpyz (L, tris[2-(5-pyrazolylmethyl)aminoethyl]amine) were characterized in both solution and solid states. A combined evaluation of potentiometric UV-Vis and EPR data provided both thermodn. and structural information on the complexes formed in solution In equimolar solution the highly stable square pyramidal CuHL and trigonal bipyramidal CuL are the dominant species at around pH 3 and 5-8, resp. Above pH 8 further deprotonation was observed (pK = 9.56), which is related to the formation of a copper(II)-bound pyrazolate anion. This creates the possibility for the formation of oligonuclear complexes, through pyrazolate bridges, and at a 3/2 Cu(II)/L ratio three trinuclear complexes were identified, similar to the copper(II)-tachpyz (N,N’,N”-tris(5-pyrazolylmethyl)-1,3,5-cis,cis-triamino-cyclohexane) system studied earlier. The trinuclear complexes of the two ligands have considerably different speciations, due to the different denticities of tripodal platforms. At the optimal pH the catechol oxidase activities of the triply deprotonated trinuclear complexes of trenpyz and tachpyz are similar, but the pH-rate constant profiles are significantly different, as a consequence of the deviations in their speciation. Consequently, the H2dtbc oxidation promoted by these trinuclear complexes can be easily controlled by the denticity of the tripodal ligands, since it affects the coordination environment of the central metal ion, which is proposed to be the main actor during the reaction.

After consulting a lot of data, we found that this compound(948552-36-1)Safety of 1H-Pyrazole-5-carbaldehyde can be used in many types of reactions. And in most cases, this compound has more advantages.

Reference:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Application of 948552-36-1. The fused heterocycle is formed by combining a benzene ring with a single heterocycle, or two or more single heterocycles. Compound: 1H-Pyrazole-5-carbaldehyde, is researched, Molecular C4H4N2O, CAS is 948552-36-1, about The first PdO nanoparticle catalyzed one pot synthesis of propargylamine through A3-coupling of an aldehyde, alkyne and amine. Author is Krishnaveni, T.; Kaveri, M. V.; Kadirvelu, K..

Palladium(II) oxide (PdO) nanoparticles (Nps) were prepared by an environmentally benign hydrothermal method with a new capping agent quercetin. The nanoparticles were characterized using FT-IR, powder XRD, TG-DTA, SEM, EDS, HR-TEM, SAED and surface area anal. (BET) to reveal the formation, crystalline structure, thermal stability, morphol., elemental composition, size, crystalline nature and surface nature, resp. Quercetin acted well as a capping agent and could yield PdO nanoparticles with a 10-15 nm size. For the first time nanosize PdO was employed as a heterogeneous catalyst for the preparation of therapeutically important propargylamines through A3 coupling reactions. A very small amount of catalyst (10 mg) was enough to complete the reaction. The isolated yields of the products were satisfying and the proposed catalyst could catalyze the reaction in the presence of a wide range of reactants. The turn over number (TON) was calculated to be high with a value of 10 625 h-1 and the turn over frequency (TOF) was also found to be excellent. The formation of propargylamines was confirmed by GC-MS anal. The PdO catalyst was recyclable and reusable for 7 successive catalytic cycles without a significant loss in yield.

After consulting a lot of data, we found that this compound(948552-36-1)Application of 948552-36-1 can be used in many types of reactions. And in most cases, this compound has more advantages.

Reference:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

The reaction of an aromatic heterocycle with a proton is called a protonation. One of articles about this theory is 《Some aldehydes of the pyrazole and 1,2,3-triazole series》. Authors are Huttel, Rudolf.The article about the compound:1H-Pyrazole-5-carbaldehydecas:948552-36-1,SMILESS:O=CC1=CC=NN1).SDS of cas: 948552-36-1. Through the article, more information about this compound (cas:948552-36-1) is conveyed.

In the formation of pyrazoles and isoxazoles from CHCCH(OEt)2 with hydrazines and hydroxylamines (Claisen, Ber. 36, 3664(1903)) it can probably be safely assumed that the aldehyde group reacts first and addition at the triple bond then takes place; in the reaction between PhCCCHO and NH2OH the oxime was isolated as an intermediate product which was isomerized to 3-phenylisoxazole only on addition of a drop of alkali. The reaction of CHCCHO (I) with substances which attack only the triple bond therefore seemed of interest. It was thought that by suitable choice of the reactants it might be possible to obtain heterocyclic aldehydes of types hitherto for the most part unknown. As a matter of fact, aliphatic diazo compounds, NH3 and aryl azides react normally at the triple bond of I and give the desired products. CH2N2 in ether dropped into I, also in ether, is immediately decolorized without evolution of N; the resulting product, C4H4ON2 (II), shows aldehyde properties and on oxidation with AgOH gives exclusively 3-pyrazolecarboxylic acid, m. 210-11°. II is therefore 3-pyrazolecarboxaldehyde. N2CHCO2Et similarly gives 5-carbethoxy-3-pyrazolecarboxaldehyde (III). These results show that the v. Auwers and Ungemach (C. A. 27, 5327) rule for the addition of aliphatic diazo compounds to RCCCO2Et also holds for the aldehydes when R = H. Addition of HN3 to I smoothly yields 2,1,3-triazole-4-carboxaldehyde (IV). PhN3 gives 1-phenyl-1,2,3-triazole-4-carboxaldehyde (V), identified by oxidation with AgNO3-NaOH to the acid (VI), m. 150°. The new aldehydes are solid, odorless and colorless substances, subliming in vacuo below their m. ps. and showing no tendency to autoxidize. They are soluble in 2 N NaOH, some even in 2 N Na2CO3, and can be recovered unchanged. This is the most interesting property of the compounds, which otherwise do not behave in any unusual manner. It is naturally observable only in the difficultly soluble II, III and V, but that the water-soluble IV also dissolves in alkali with salt formation is shown by the fact that it cannot be extracted from the NaOH or even Na2CO3 solution with ether. Since V has no H on a N atom, it must be the aldehyde group of these compounds which is responsible for the salt formation. The question of their structure in alk. solution is reserved for a later investigation. II and III are stable toward 2 N NaOH for a long time and can be recovered quantitatively. III is also stable for a short time but on longer standing in the alk. solution the ester group is saponified and the free acid is obtained. V is also an exception; it can be recovered unchanged only if the alk. solution is immediately neutralized; otherwise, in 10-20 min. the apparently greatly “”strained”” alkali salt stabilizes itself by disproportionation to VI and 1-phenyl-4-hydroxymethyl-1,2,3-pyrazole (VII), insoluble in alkali. Acrolein also immediately decolorizes CH2N2 without evolution of N and in ice there seps. a colorless, flocculent (often partly crystalline) precipitate which on warming to room temperature or treatment with acids or alkalies is immediately altered (probably isomerized), turning yellow or red. It has not as yet been possible to verify the assumption that it is a pyrazolinecarboxaldehyde; oxidation gave neg. results; addition of carbonyl reagents prevented the appearance of color on warming to room temperature but no crystalline product could be isolated. I b720 53.5-5°; it dissolves in water and is clear in all organic solvents except the aromatic hydrocarbons. It is not advisable to carry out reactions with it in benzene; thus, with PhN3 it gave only 33% V as against 90% in ether. The freshly prepared, distilled, colorless I turns yellow quite rapidly at room temperature and on long standing partly polymerizes and becomes dark brown. It also partly polymerizes in water, with deposition of an insoluble brown powder. When refluxed in water it forms a brown flocculent deposit in 10 min. and in 2 hrs. its odor is hardly perceptible. Acids and weak alkalies (NH3, Na2CO3) materially accelerate the polymerization. Whereas NaOH in water gives C2H2 and HCO2Na, in acetone or cyclohexane it forms a crystalline di-Na salt of a trimer of I, leaflets easily soluble in water, reprecipitated by alc., gives a red-violet FeCl3 reaction, reduces AgNO3-NH3, gives on decomposition with H2SO4 and exhaustive extraction with ether the free trimer, C9H8O4 (= 3 I + H2O), prismatic needles from acetone, turns brown 135°, m. 141°, reduces Tollens reagent and gives a violet-red FeCl3 reaction but no yellow color with C(NO2)4. II (84% yield), m. 149-50° from water, reddens fuchsin-SO2, reduces NH3-AgNO3, gives a neg. FeCl3 reaction, takes up Br in AcOH only slowly, reacts neutral to litmus in hot water. III (86%), m. 135° after crystallization from alc. or sublimation in vacuo (at 130°); free acid, m. 245° (decomposition), oxidized by boiling HNO3 (1:1) to 3,5-pyrazoledicarboxylic acid, m. 289° (decomposition). IV (90% crude and 78% pure, sublimed product), m. 141-2° from water or alc. V (75% from I and 1 mol. PhN3 refluxed 6 hrs. in CHCl3), m. 99-100° from benzene-petr. ether or water. VII (250 mg. from 500 mg. V allowed to stand 4 hrs. in 10 cc. of 2 N NaOH), m. 110-11° from water.

After consulting a lot of data, we found that this compound(948552-36-1)SDS of cas: 948552-36-1 can be used in many types of reactions. And in most cases, this compound has more advantages.

Reference:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Computed Properties of C4H4N2O. The reaction of aromatic heterocyclic molecules with protons is called protonation. Aromatic heterocycles are more basic than benzene due to the participation of heteroatoms. Compound: 1H-Pyrazole-5-carbaldehyde, is researched, Molecular C4H4N2O, CAS is 948552-36-1, about Synthesis of 2-(3-pyrazolyl)imidazo[4,5-f][1,10]phenanthroline. Author is Lin, Long; Wu, Jian-fang; Pan, Wen-long; Wu, Jian-zhong.

A new ligand, 2-(1H-pyrazol-3-yl)imidazo[4,5-f][1,10]phenanthroline (I), was synthesized from 1,10-phenanthrolinequinone (i.e., 1,10-phenanthroline-5,6-dione) and 1H-pyrazole-3-carboxaldehyde. The structure was characterized by 1H NMR, IR and MS (ESI). The electronic absorption and fluorescence spectra of I were also measured.

Although many compounds look similar to this compound(948552-36-1)Computed Properties of C4H4N2O, numerous studies have shown that this compound(SMILES:O=CC1=CC=NN1), has unique advantages. If you want to know more about similar compounds, you can read my other articles.

Reference:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Most of the compounds have physiologically active properties, and their biological properties are often attributed to the heteroatoms contained in their molecules, and most of these heteroatoms also appear in cyclic structures. A Journal, European Journal of Organic Chemistry called Molecular Structure, Intramolecular Hydrogen Bonding, Solvent-Induced Isomerization, and Tautomerism in Azolylmethylidene Derivatives of 2-Indanone, Author is Sigalov, Mark V.; Shainyan, Bagrat A.; Chipanina, Nina N.; Oznobikhina, Larisa P., which mentions a compound: 948552-36-1, SMILESS is O=CC1=CC=NN1, Molecular C4H4N2O, Application of 948552-36-1.

Bis adducts of 2-indanone with 1H-pyrrole-2-carbaldehyde, 1H-imidazole-2-carbaldehyde, 1H-imidazole-5-carbaldehyde, and 1H-indazole-3-carbaldehyde 3-6 were synthesized and the intertwined processes of tautomeric NH proton transfer, intra- and intermol. H-bond rupture and formation, and Z/Z, Z/E, and E/E-isomerization were studied by NMR and FTIR spectroscopy and by conducting DFT calculations Pyrrole derivative 3 both in chloroform and in DMSO exists exclusively as the Z,Z-isomer stabilized by two intramol. N-H···O hydrogen bonds. For derivatives 4-6, the isomeric composition depends on the solvent so that in polar media such as DMSO and pyridine the Z,E- and E,E-isomers predominate. The driving force for isomerization of 4-6 is stabilization of the Z,E- and E,E-isomers in basic polar solvents due to formation of intermol. NH···B and intramol. C-H···N hydrogen bonds. The suggested mechanism of isomerization includes proton transfer from nitrogen to oxygen in the Z-moiety followed by rotation about the C-C bond in the formed enol and isomerization of the latter to the E-moiety of the ketone tautomer.

Although many compounds look similar to this compound(948552-36-1)Application of 948552-36-1, numerous studies have shown that this compound(SMILES:O=CC1=CC=NN1), has unique advantages. If you want to know more about similar compounds, you can read my other articles.

Reference:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Computed Properties of C4H4N2O. The protonation of heteroatoms in aromatic heterocycles can be divided into two categories: lone pairs of electrons are in the aromatic ring conjugated system; and lone pairs of electrons do not participate. Compound: 1H-Pyrazole-5-carbaldehyde, is researched, Molecular C4H4N2O, CAS is 948552-36-1, about Structure-Based Drug Design of Novel Potent and Selective Tetrahydropyrazolo[1,5-a]pyrazines as ATR Inhibitors. Author is Barsanti, Paul A.; Aversa, Robert J.; Jin, Xianming; Pan, Yue; Lu, Yipin; Elling, Robert; Jain, Rama; Knapp, Mark; Lan, Jiong; Lin, Xiaodong; Rudewicz, Patrick; Sim, Janet; Taricani, Lorena; Thomas, George; Xiao, Linda; Yue, Qin.

A saturation strategy focused on improving the selectivity and physicochem. properties of ATR inhibitor HTS hit I led to a novel series of highly potent and selective tetrahydropyrazolo[1,5-a]pyrazines, e.g. II. Use of PI3Kα mutants as ATR crystal structure surrogates was instrumental in providing cocrystal structures to guide the medicinal chem. designs. Detailed DMPK studies involving cyanide and GSH as trapping agents during microsomal incubations, in addition to deuterium-labeled compounds as mechanistic probes uncovered the mol. basis for the observed CYP3A4 TDI in the series.

Although many compounds look similar to this compound(948552-36-1)Computed Properties of C4H4N2O, numerous studies have shown that this compound(SMILES:O=CC1=CC=NN1), has unique advantages. If you want to know more about similar compounds, you can read my other articles.

Reference:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem