4681-81-6

Basic information

• Product Name: 2,3,4,5-tetraethylbenzenesulfonic acid
• CAS NO: 4681-81-6
• Molecular Formula: C₁₄H₂₂O₃S
• Molecular Weight: 270.3877
• Mol File: 4681-81-6.mol
• Article Data: 1

Chemical Properties

• Density: 1.11g/cm³
• Refractive Index: 1.52
• CAS DataBase Reference: 2,3,4,5-tetraethylbenzenesulfonic acid(CAS DataBase Reference)
• NIST Chemistry Reference: 2,3,4,5-tetraethylbenzenesulfonic acid(4681-81-6)
• EPA Substance Registry System: 2,3,4,5-tetraethylbenzenesulfonic acid(4681-81-6)

Safety Data

• Hazardous Substances Data: 4681-81-6(Hazardous Substances Data)

Usage

General Description

2,3,4,5-tetraethylbenzenesulfonic acid is an organic compound and a sulfonic acid derivative of tetraethylbenzene. It is a powerful acid and is commonly used as a catalyst in various organic reactions. The compound has four ethyl groups attached to the benzene ring, providing it with significant steric hindrance, making it a bulky and effective acid. It is also used as an intermediate in the synthesis of various pharmaceuticals, dyes, and agrochemicals. Additionally, 2,3,4,5-tetraethylbenzenesulfonic acid is used as a corrosion inhibitor and as a component in electrolytes for lithium-ion batteries.

Upstream product

• 38842-05-6 1,2,3,5-tetraethylbenzene 
• 635-81-4 1,2,4,5-tetraethylbenzene 
• 74-96-4 ethyl bromide 
• 71-43-2 benzene 
• 605-01-6 pentaethylbenzene 

Relevant articles and documents

Preparation and conformation of octaethylbiphenylene

Dimerization of tetraethylbenzyne (generated by reaction of 1,2-dibromo-3,4,5,6-tetraethylbenzene (8) with 1 equiv of BuLi) afforded in low yield octaethylbiphenylene (3), together with a major product which was characterized as 2,3,4,5,3',4',5'-heptaethyl-2'-vinylbiphenyl (9). X-ray diffraction indicates that biphenylene 3 adopts in the crystal a conformation of approximate C(2h) symmetry with the ethyl groups within each phenylene ring arranged in an alternated up-down fashion. Notably, pairs of vicinal ethyl groups located at peri positions are oriented in a syn arrangement in the crystal. Low temperature NMR spectroscopy is consistent with the presence in solution of either the crystal conformation or a fully alternated conformation lacking any syn interaction. Molecular mechanics (MM3), semiempirical (AM1, PM3), and ab initio calculations indicate that the crystal conformation is a high energy form, and that the lowest energy conformation is the fully alternated form. The topomerization barrier of the methylene protons of the ethyl groups of 3 is 9.4 ± 0.1 kcal mol-1, which is between the rotational barriers of 8 and 1,2,3,4-tetraethylbenzene 7 (9.9 ± 0.1 and 8.2 ± 0.1 kcal mol-1, respectively). The similarity in rotational barriers suggests that a given tetraethylphenylene subunit does not markedly affect the rotational barrier of the ethyl groups of the other subunit.