1,4-Benzoquinone dioxime
[CAS 105-11-3]

Identification

• Classification: Chemical reagent >> Organic reagent >> Oxime
• Name: 1,4-Benzoquinone dioxime
• Synonyms: p-Quinone dioxime; p-Benzoquinone dioxime
• Molecular Formula: C₆H₆N₂O₂
• Molecular Weight: 138.12
• CAS Registry Number: 105-11-3
• EC Number: 203-271-5
• SMILES: C1=CC(=CC=C1NO)N=O

Properties

• Density: 1.3±0.1 g/cm³ Calc.^*, 1.49 g/mL (Expl.)
• Melting point: 223 °C (Decomposes) (Expl.)
• Boiling point: 303.0±42.0 °C 760 mmHg (Calc.)^*
• Flash point: 182.5±17.1 °C (Calc.)^*
• Solubility: water <0.01 g/100 mL 22.5 °C (Expl.)
• Index of refraction: 1.594 (Calc.)^*

^* Calculated using Advanced Chemistry Development (ACD/Labs) Software.

Safety Data

• Hazard Symbols: GHS07;GHS08 Warning
• Risk Statements: H302-H351
• Safety Statements: P281-P264-P301+P312-P308+P313-P405-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Acute toxicity	Acute Tox.	4	H302
Carcinogenicity	Carc.	2	H351
Germ cell mutagenicity	Muta.	2	H341
Chronic hazardous to the aquatic environment	Aquatic Chronic	2	H411
Skin sensitization	Skin Sens.	1A	H317
Eye irritation	Eye Irrit.	2	H319
Flammable solids	Flam. Sol.	2	H228
Skin irritation	Skin Irrit.	2	H315
Specific target organ toxicity - single exposure	STOT SE	3	H335
Explosives	Expl.	1.4	H204
Acute toxicity	Acute Tox.	3	H301
Acute toxicity	Acute Tox.	4	H332
Acute toxicity	Acute Tox.	4	H312
Flammable solids	Flam. Sol.	1	H228
Serious eye damage	Eye Dam.	1	H318
Self-reactive substances or mixtures	Self-react.	D	H242

chemBlink Chemical Story

1,4-Benzoquinone dioxime became important in rubber chemistry because useful elastomers require a controlled network of crosslinks. Raw polymer chains can slide too freely; vulcanization connects them so the material can stretch and recover rather than flow permanently.

Quinone dioxime systems were used especially with butyl rubber and other relatively low-unsaturation elastomers. Historical industrial literature describes p-quinone dioxime as a vulcanizing or vulcanization-accelerating agent, often used with suitable activating or oxidizing components.

The central materials problem is balance. Too few crosslinks allow creep and deformation; too many make the material hard and brittle. The familiar properties of rubber therefore emerge not simply from long chains, but from how those chains are connected.

References:
NIST Chemistry WebBook. 1,4-Benzoquinone dioxime, CAS 105-11-3.
National Cancer Institute Technical Report 179.

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