2127-14-2

Basic information

• Product Name: (1-methylpyridin-4(1H)-ylidene)-N-oxomethanaminium
• CAS NO: 2127-14-2
• Molecular Formula: C₇H₉N₂O*I
• Molecular Weight: 137.1586
• Mol File: 2127-14-2.mol
• Article Data: 8

Chemical Properties

• Boiling Point: 187.7°C at 760 mmHg
• Flash Point: 67.3°C
• Vapor Pressure: 0.621mmHg at 25°C
• CAS DataBase Reference: (1-methylpyridin-4(1H)-ylidene)-N-oxomethanaminium(CAS DataBase Reference)
• NIST Chemistry Reference: (1-methylpyridin-4(1H)-ylidene)-N-oxomethanaminium(2127-14-2)
• EPA Substance Registry System: (1-methylpyridin-4(1H)-ylidene)-N-oxomethanaminium(2127-14-2)

Safety Data

• Hazardous Substances Data: 2127-14-2(Hazardous Substances Data)

Usage

General Description

The chemical compound (1-methylpyridin-4(1H)-ylidene)-N-oxomethanaminium, also known as Meldrum's acid, is a versatile organic building block with a wide range of applications in organic synthesis and pharmaceuticals. It is a stable and colorless solid that is soluble in polar solvents such as water and alcohols. Meldrum's acid is often used as a precursor in the synthesis of various pharmaceutical compounds and agrochemicals. It can also act as a versatile nucleophilic reagent and can be easily modified to introduce a wide range of functional groups. Meldrum's acid has also been studied for its potential applications in materials science, such as in the synthesis of polymers and nanoparticles. Overall, Meldrum's acid is an important and valuable chemical compound in the field of organic chemistry.

Upstream product

• 872-85-5 pyridine-4-carbaldehyde 
• 1637-52-1 4-pyridinealdoxime 
• 74-88-4 methyl iodide 
• 696-54-8 pyridine-4-aldoxime 

Downstream Products

• 58822-12-1 4-pyridinealdoxime methchloride 
• 57092-56-5 C₉H₁₁N₂O₂⁽¹⁺⁾*I^(1-) 
• 14609-74-6 p-nitrophenolate 

Relevant articles and documents

QUATERNARY HETEROARENIUM ALDOXIMES AS CATALYSTS FOR CLEAVAGE OF PHOSPHATE ESTERS

!-Methyl- (Ia - Id) and 1-dodecyl-2-, 3- and 4-hydroxyiminomethylpyridinium salts (Ie - Ih), as well as 1-methyl- (IIa) and 1-dodecyl-3-hydroxyiminomethylpyridazinium salts (IIb, IIc), were synthesized as catalysts for hydrolytic cleavage of organophosphates.The activities of the prepared catalysts were evaluated by measuring rate constants of hydrolysis of 4-nitrophenyl diphenyl phosphate (PNPDPP) under conditions of a pseudo-first-order reaction.The observed reactivity of pyridinium aldoximes Ia - Ih towards PNPDPP in neutral or slightly basic aqueous solutions (pH 7.2 and 7.8) depends on the acidity of the hydroxyimino group.The cleavage of PNPDPP is strongly accelerated in solutions of 1-dodecylhydroxyiminomethylpyridinium salts Ie - Ih above their critical micellar concentration (CMC).Considerable effect on the velocity of PNPDPP cleavage was observed when quaternary pyridinium aldoximes Ie - Ih were comicellized with inert cationic tenside hexadecyltrimethylammonium bromide (CTAB). 1-Dodecyl-3-hydroxyiminomethylpyridazinium salts IIb and IIc were unstabel in aqueous solutions under the above-mentioned conditions.

Synthesis of 1,2,5,6-/1,2,3,6-Tetrahydropyridinyl-tetrahydrocyclopentaisoxazole Derivatives

Fused tetrahydrocyclopenta-isoxazoles were synthesized by 1,3-dipolar cycloaddition reactions with pyridinealdoxime or tetrahydropyridinealdoxime and cycloalkenes.

Spectroscopic and structural insights into N-substituted pyridinium-4-aldoximes and their pentacyanoferrate(II) complexes

Comparative kinetic and equilibrium studies on the formation and dissociation of three mono- and one bis-pyridinium-4-aldoxime pentacyanoferrate(II) complexes have been carried out in aqueous solutions at 25 °C and I = 0.1 M. The synthesis, spectroscopic and thermal characterization of a new N-methylpyridinium-4-aldoxime pentacyanoferrate(II) complex is presented. The obtained values for the equilibrium constants, identified as apparent formation constants (βf/M-1) along with kinetic parameters, the formation (kf/M-1 s-1) and dissociation (kd/s-1) rate constants indicated the behaving of all protonated pyridinium-4-aldoximes as weak π-acceptors. The pH-dependence of the dissociation rates has been analyzed in terms of ionization abilities of the coordinated ligands. The magnitude of the dissociation rates suggested that both protonated and deprotonated ligand forms are effective σ-donors that bind to the [Fe(CN)5]3- moiety through the nitrogen atom. The deprotonation of the coordinated aldoxime group leads to the reduced lability of the complexes due to increased σ-donor capability of aldoximato nitrogen causing the strengthened of the iron(II)-nitrogen bond. The values of dissociation activation parameters, ΔH? and ΔS?, are found to be consistent with the S N1 dissociative type of mechanism. The spectroscopic data (FT-IR, NMR and UV-Vis) of the isolated coordinated pentacyanoferrates(II) conforms with the weak π-acceptor properties of the pyridinium-4-aldoxime ligands. A detailed structural characterization of the iodide and chloride salt of N-methylpyridinium-4-aldoxime was also presented using NMR, FT-IR and UV-Vis spectroscopy, as well as X-ray diffraction.

Preparation and in vitro evaluation of monoquaternary inhibitors of brain cholinesterases

Acetylcholinesterase inhibitors are currently of high interest due to the many reasons. Among them, Alzheimer's disease drugs are of great interest. In this study, eleven monoquaternary pyridinium salts substituted by different groups (electron donors and