1,2,4,5-Tetrabromobenzene

Base Information

• Chemical Name: 1,2,4,5-Tetrabromobenzene
• CAS No.: 636-28-2
• Molecular Formula: C6H2Br4
• Molecular Weight: 393.698
• Hs Code.: 29039990
• European Community (EC) Number: 211-253-3
• NSC Number: 27002
• UNII: M25DK66LCZ
• DSSTox Substance ID: DTXSID7060910
• Nikkaji Number: J2.098B
• Wikipedia: 1,2,4,5-Tetrabromobenzene
• Wikidata: Q27283377
• Mol file: 636-28-2.mol

Synonyms:1,2,4,5-tetraBB;1,2,4,5-tetrabromobenzene

Chemical Property of 1,2,4,5-Tetrabromobenzene

Chemical Property:

• Appearance/Colour: brown crystalline needles
• Vapor Pressure: 0.000385mmHg at 25°C
• Melting Point: 180-182 °C(lit.)
• Refractive Index: 1.661
• Boiling Point: 327.5 °C at 760 mmHg
• Flash Point: 148.5 °C
• PSA: 0.00000
• Density: 2.553 g/cm³
• LogP: 4.73660
• Storage Temp.: Sealed in dry,Room Temperature
• Solubility.: Soluble in alcohol, benzene, and ether (Weast, 1986)
• Water Solubility.: Insoluble in water.
• XLogP3: 5.1
• Hydrogen Bond Donor Count: 0
• Hydrogen Bond Acceptor Count: 0
• Rotatable Bond Count: 0
• Exact Mass: 393.68490
• Heavy Atom Count: 10
• Complexity: 90.3

Purity/Quality:

≥99% ^*data from raw suppliers

1,2,4,5-Tetrabromobenzene ^*data from reagent suppliers

Safty Information:

• Pictogram(s): Xi
• Hazard Codes: Xi
• Statements: 36/37/38
• Safety Statements: 26-37/39

MSDS Files:

SDS file from LookChem

Total 1 MSDS from other Authors

Useful:

• Canonical SMILES: C1=C(C(=CC(=C1Br)Br)Br)Br
• General Description: 1,2,4,5-Tetrabromobenzene is a polyhaloarene that serves as a precursor in reactions involving organolithium reagents, where it can act as a di-aryne equivalent. Its reactivity is influenced by substituents, with electron-withdrawing groups favoring the formation of stable dilithio intermediates at low temperatures, which subsequently eliminate lithium bromide to generate arynes at higher temperatures. The para orientation of lithium atoms in these intermediates minimizes charge repulsion, making it useful for synthesizing complex aromatic structures such as anthracenes and phenanthrenes.

Technology Process of 1,2,4,5-Tetrabromobenzene

There total 36 articles about 1,2,4,5-Tetrabromobenzene which guide to synthetic route it. The literature collected by LookChem mainly comes from the sharing of users and the free literature resources found by Internet computing technology. We keep the original model of the professional version of literature to make it easier and faster for users to retrieve and use. At the same time, we analyze and calculate the most feasible synthesis route with the highest yield for your reference as below:

synthetic route:

Reference yield: 87.0%

1.4-dibromobenzene (106-37-6) → 1,2,4,5-tetrabromobenzene (636-28-2)

Guidance literature:

With bromine; iron; In chloroform; at 20 - 60 ℃; for 72h;

DOI:10.1021/acs.joc.9b01317

Reference yield: 80.0%

benzene (71-43-2,26181-88-4,54682-86-9,13967-78-7,174973-66-1) → 1,2,4,5-tetrabromobenzene (636-28-2)

Guidance literature:

With iron(III) chloride; bromine; In chloroform; at 0 - 45 ℃;

DOI:10.1002/chem.201100443

Reference yield: 11.0%

benzene (71-43-2,26181-88-4,54682-86-9,13967-78-7,174973-66-1) → 1,2,4,5-tetrabromobenzene (636-28-2) + 1.4-dibromobenzene (106-37-6) + 1,2,4-tribromobenzene (615-54-3)

Guidance literature:

With oxygen; iron; 1,1-dibromomethane; at 40 ℃; for 2h; Overall yield = 520 mg;

DOI:10.1002/asia.201200322

upstream raw materials:

cyclohexane

1.4-dibromobenzene

hexabromobenzene

1,5-diamino-2,4-dibromobenzene

Downstream raw materials:

1,2,4,5-tetrabromo-3-nitrobenzene

1,2,4,5-tetrabromo-3,6-dinitro-benzene

2,4,5-tribromophenol

tert-butyl-(2,4,5-tribromo-phenyl)-sulfide

Refernces

THE DILITHIATION MECHANISM IN THE REACTIONS OF POLYHALOARENES AS DI-ARYNE EQUIVALENTS

10.1016/S0040-4039(00)94183-2

The research investigates the dithiolation mechanism in the reactions of polyhaloarenes as di-aryne equivalents. The purpose is to understand how different substituents on polyhaloarenes influence the reaction pathways when treated with organolithium reagents. The key chemicals used include 1,2,4,5-tetrabromobenzenes, furan, organolithium reagents like n-BuLi, and various electrophiles such as methanol, iodine, and (CH3)2SO4. The study concludes that the reaction mechanism can proceed via either a monolithio intermediate (Path A) or a dilithio intermediate (Path B), depending on the nature of the substituents. Specifically, when the substituent is an electron-withdrawing group like chlorine, the reaction proceeds via Path B, forming a stable dilithio intermediate. This intermediate is stable at low temperatures but eliminates lithium bromide at higher temperatures to form arynes. The findings suggest that the para orientation of lithium atoms in these dilithio compounds is due to the minimization of repulsion between negative charges. The results have implications for the synthesis of complex aromatic compounds like anthracenes and phenanthrenes from readily available precursors.