Skip to content
diazomethane

Structure via PubChem · Public domain (PubChem)

EntityQ413683· pop 27· linked from 156 articles

diazomethane

Sign in to save

Also known as Azimethylene, Azomethylene, Diazirine, acomethylene, EINECS 206-382-7, diazonium methylide

Diazomethane is an organic chemical compound with the formula CH2N2, discovered by German chemist Hans von Pechmann in 1894. It is the simplest diazo compound. In the pure form at room temperature, it is an extremely sensitive explosive yellow gas; thus, it is almost universally used as a solution in diethyl ether. The compound is a popular methylating agent in the laboratory, but it is too hazardous to be employed on an industrial scale without special precautions. Use of diazomethane has been significantly reduced by the introduction of the safer and equivalent reagent trimethylsilyldiazomet

Chemical data

Formula
CH2N2
Molecular weight
42.04 g/mol
IUPAC name
diazomethane
SMILES
C=[N+]=[N-]
InChIKey
YXHKONLOYHBTNS-UHFFFAOYSA-N
XLogP
1.6
Polar surface area
2 Ų
H-bond donors
0
H-bond acceptors
1
Formal charge
0

via PubChem

Research

1,568 papers

via PubMed

Wikidata facts

Mass
42.022
Show 11 more facts
NIOSH Pocket Guide ID
0182
chemical formula
CH₂N₂
immediately dangerous to life or health
3.44
melting point
-145
boiling point
-23
vapor pressure
1
ionization energy
9.00
time-weighted average exposure limit
0.4
canonical SMILES
C=[N+]=[N-]
Commons category
Diazomethane
electric dipole moment
1.50
Sources (4)

via Wikidata · CC0

~7 min read

Article

10 sections
Contents
  • Use
  • Preparation
  • Laboratory scale
  • Industrial use
  • Analysis
  • Related compounds
  • Safety
  • Isomers
  • References
  • External links

Diazomethane is an organic chemical compound with the formula CH2N2, discovered by German chemist Hans von Pechmann in 1894. It is the simplest diazo compound. In the pure form at room temperature, it is an extremely sensitive explosive yellow gas; thus, it is almost universally used as a solution in diethyl ether. The compound is a popular methylating agent in the laboratory, but it is too hazardous to be employed on an industrial scale without special precautions. Use of diazomethane has been significantly reduced by the introduction of the safer and equivalent reagent trimethylsilyldiazomethane.

==Use== For safety and convenience diazomethane is always prepared as needed as a solution in ether and used as such. It converts carboxylic acids to methyl esters and phenols into their methyl ethers. The reaction is thought to proceed via proton transfer from carboxylic acid to diazomethane to give a methyldiazonium cation, which reacts with the carboxylate ion to give the methyl ester and nitrogen gas. Labeling studies indicate that the initial proton transfer is faster than the methyl transfer step. Since proton transfer is required for the reaction to proceed, this reaction is selective for the more acidic carboxylic acids (pKa ~ 5) and phenols (pKa ~ 10) over aliphatic alcohols (pKa ~ 15). center|frameless|500x500px

Gallery (11)

Connections

Categories