4-Acetamidobenzenesulfonyl azide
[CAS# 2158-14-7]

Identification

• Classification: Organic raw materials >> Hydrocarbon compounds and their derivatives >> Hydrocarbon sulfonate
• Name: 4-Acetamidobenzenesulfonyl azide
• Synonyms: N-(4-azidosulfonylphenyl)acetamide
• Molecular Formula: C₈H₈N₄O₃S
• Molecular Weight: 240.24
• CAS Registry Number: 2158-14-7
• EC Number: 606-801-7
• SMILES: CC(=O)NC1=CC=C(C=C1)S(=O)(=O)N=[N+]=[N-]

Properties

• Melting point: 107-111 ºC

Safety Data

• Hazard Symbols: GHS07 Warning
• Hazard Statements: H315-H319-H335
• Precautionary Statements: P261-P264-P264+P265-P271-P280-P302+P352-P304+P340-P305+P351+P338-P319-P321-P332+P317-P337+P317-P362+P364-P403+P233-P405-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Skin irritation	Skin Irrit.	2	H315
Eye irritation	Eye Irrit.	2	H319
Specific target organ toxicity - single exposure	STOT SE	3	H335
Germ cell mutagenicity	Muta.	2	H341

Discovory and Applicatios

4-Acetamidobenzenesulfonyl azide, commonly known as PABSA or acetamidobenzenesulfonyl azide, is a versatile organic compound that is widely used in organic synthesis. Its major applications include use as a reagent in the synthesis of various pharmaceuticals, agrochemicals, and polymeric materials.

The compound 4-Acetamidobenzenesulfonyl azide was first synthesized and characterized in the mid-20th century. Its discovery was part of extensive research into developing new sulfonyl azides, which are compounds containing a sulfonyl functional group (SO₂) and an azide group (N₃). These compounds have attracted great interest due to their reactivity and usefulness in various chemical reactions, especially in the formation of new carbon-nitrogen bonds.

4-Acetamidobenzenesulfonyl azide has the chemical formula C₈H₈N₄O₃S and occurs as a crystalline solid. Its structural feature is an acetamido group (NHCOCH₃) attached to a benzene ring, which is also bonded to a sulfonyl azide group. The azide functional group imparts it with remarkable reactivity, making it useful for a variety of chemical transformations.

The most important application of 4-acetamidobenzenesulfonyl azide is as a reagent in organic synthesis. It serves as a source of nitrene intermediates, allowing it to participate in a variety of reactions, such as: PABSA is used in click chemistry, and it reacts with alkynes to form 1,2,3-triazoles, which are valuable in pharmaceuticals and materials science. It can generate nitrene intermediates that insert into C-H and N-H bonds, thereby facilitating the synthesis of amines, amides, and other nitrogen-containing compounds. PABSA can transfer the sulfonyl group to nucleophiles to form sulfonamides and sulfonates, which are essential subjects in medicinal chemistry.

In the pharmaceutical industry, 4-acetamidobenzenesulfonyl azide is used to synthesize a variety of drugs and drug intermediates. Its reactivity allows for the efficient construction of complex molecular structures required for active pharmaceutical ingredients (APIs). The formation of 1,2,3-triazoles via azide-alkyne cycloaddition is particularly noteworthy as these structures are found in numerous therapeutic agents with antiviral, antibacterial, and anticancer activities.

PABSA is also used in the modification of polymers and the development of new materials. The introduction of azido functionality into the polymer backbone can create crosslinked networks and functionalized surfaces. These modifications can enhance the properties of the polymer, such as its mechanical strength, thermal stability, and biocompatibility, making it suitable for advanced applications in medical devices, coatings, and nanomaterials.

While 4-acetamidobenzenesulfonyl azide is a valuable reagent, it must be handled with care as its reactive azide group can be explosive under certain conditions. Appropriate safety measures, including the use of protective equipment and working in well-ventilated areas, are essential. In addition, PABSA should be stored away from heat and ignition sources.

References

2005. Simple preparation of alpha-diazo esters. The Journal of Organic Chemistry, 70(6).
DOI: 10.1021/jo048011o

2021. Effect of Electron-Deficient Azide Substrates: Acyl, Phosphoryl, and Sulfonyl Azides. Science of Synthesis.
URL: SD-235-00016

2017. Regioselective synthesis of some new 1,4-disubstituted sulfonyl-1,2,3-triazoles and their antibacterial activity studies. Medicinal Chemistry Research, 26(10).
DOI: 10.1007/s00044-017-1926-6