Physical Properties:

Methyl Sulfonyl Azide (CAS 1516-70-7, CH3N3O2S) Is a colorless to low-melting white solid (18–20∘C ). It is a highly reactive, potentially explosive reagent used in organic synthesis for diazo transfer, decomposing at temperatures above 120–130∘C.

Key Properties and Characteristics:

Molecular Weight: 121.12g/mol

Density: 1.4361g/cm3

Melting Point: 18–20∘C

Boiling Point: 59–60∘C

Reactivity: High, acts as a transfer reagent, generating large gas volumes upon decomposition

Storage: Store cold (<0∘C recommended), in the dark, away from heat and friction

Handling: Use in a fume hood; avoid contact with skin and eyes

Safety Precautions:

• Explosive Risk: Requires caution to avoid impact or friction
• Decomposition: Exothermic decomposition starts around 120⁰C
• Safety Measures: Utilize appropriate personal protective equipment and spark-proof tools

Primary Synonyms and Identifiers

Preferred IUPAC Name: Methanesulfonyl azide

Common Name: Mesyl azide

Other Names:

Methane sulfonyl azide

Methanesulfonic acid azide

Methylsulfonyl azide

N-diazomethanesulfonamide

Methansulfonylazid (German)

メタンスルホニルアジド (Japanese)

메탄 설포 닐아 지드 (Korean)

Identifiers

CAS Number: 1516-70-7

PubChem CID: 556271

ChemSpider ID: 483609

Molecular Formula: 𝐶𝐻3𝑁3𝑂2𝑆

Molecular Weight: 121.12 g/mol

Methanesulfonyl azide (CAS 1516-70-7), or mesyl azide, is a specialized reagent primarily used in organic synthesis for diazo-transfer reactions, creating 𝛼-diazo carbonyl compounds and sulfonylazides/ureas. It is essential for click chemistry (CuAAC reactions) to form triazoles and serves as a reactant in medicinal chemistry to produce pharmaceutical intermediates.

Key Uses and Applications:

• Organic Synthesis & Diazo Transfer:It is a key reagent for introducing a diazo group (=𝑁2) onto active methylene compounds, facilitating the formation of 𝛼-diazo carbonyl compounds.
• Click Chemistry:Employed in copper-catalyzed azide-alkyne cycloaddition (CuAAC) reactions to synthesize triazole rings, often used in drug discovery.
• Pharmaceutical Intermediates:Used to create sulfonylguanidines and sulfonylureas, which are intermediates in the development of various pharmaceutical and agrochemical products.
• Chemical Research:Used in research for nitrene generation (via photolysis) and in the synthesis of specialized organic molecules.

Important Safety Information:
Due to its nature as a high-energy compound, methanesulfonyl azide is considered explosive and requires strict safety protocols, including specialized handling or in situ generation to minimize risks.