(E)-1,2-Bis(4-bromo-2-methoxyphenyl)diazene

1. Basic information

Chinese name: (E)-1,2-Bis(4-bromo-2-methoxyphenyl)diazene

English name: (E)-1,2-Bis(4-bromo-2-methoxyphenyl)diazene

Alias: (E)-Bis(4-bromo-2-methoxyphenyl)azo compound; (E)-4,4'-dibromo-2,2'-dimethoxyazobenzene

Chemical formula: C₁₄H₁₂Br₂N₂O₂

Molecular weight: 400.07 g/mol

CAS number: To be confirmed (the core structure is an azo double bond of (E) configuration connecting two substituted benzene rings, which belongs to azo derivatives)

Structural features: The molecule contains an azo group of (E) configuration (-N=N-), with a 4-bromo-2- Methoxyphenyl, methoxy (-OCH₃) is located at the 2nd position of the benzene ring, bromine (Br) is located at the 4th position, the azo double bond forms a conjugated system with the benzene ring, and there are cis-trans isomers (this product is E-type, and the groups at both ends of the azo bond are arranged in a trans position).

2. Physical and chemical properties

Appearance and state:

Orange to dark red crystalline powder, the crystal is dark due to the conjugated structure, and there is no special smell (dry state).

Melting point: 118-122℃ (decomposition), boiling point: easy to decompose at high temperature (azo bond breaks and releases nitrogen), density: 1.72 g/cm³ (estimated).

Solubility:

Slightly soluble in water (solubility < 0.1 g/L at 25℃), easily soluble in organic solvents such as chloroform, dichloromethane, acetone, soluble in hot ethanol, insoluble in petroleum ether.

Chemical properties:

Azo bond reactivity:

Azo groups are easily decomposed to generate free radicals (releasing N₂) under light or heating, and can be used as polymerization initiators (similar to azobisisobutyronitrile);

Can be reduced to amino compounds (such as SnCl₂/HCl system to 4-bromo-2-methoxyaniline).

Substituent reactivity:

Methoxy is an electron-donating group, which enhances the electrophilic substitution activity of the benzene ring (the substitution site may be at position 3 or 5 of the benzene ring);

Bromo atoms can undergo nucleophilic substitution (such as reacting with sodium cyanide to generate cyano groups, requiring high temperature or catalyst);

Azo bonds can be added with nucleophilic reagents (such as amines, thiols) to generate hydrazones or other derivatives.

Stability: Stable under light-proof conditions, accelerated decomposition by light or high temperature (>100℃), avoid contact with strong reducing agents and strong acids (may cause azo bond breakage or benzene ring substitution reactions).