trans-4-Methycyclohexyl isocyanate
[CAS# 32175-00-1]

Identification

• Classification: Chemical reagent >> Organic reagent >> Cyanate ester / isocyanate
• Name: trans-4-Methycyclohexyl isocyanate
• Synonyms: trans-1-Isocyanato-4-methyl-cyclohexane; Isocyanic acid trans-4-methylcyclohexyl ester
• Molecular Formula: C₈H₁₃NO
• Molecular Weight: 139.19
• CAS Registry Number: 32175-00-1
• EC Number: 608-715-5
• SMILES: CC1CCC(CC1)N=C=O

Properties

• Density: 1.0±0.1 g/cm³, Calc.^*
• Index of Refraction: 1.519, Calc.^*
• Boiling Point: 182.2±9.0 °C (760 mmHg), Calc.^*
• Flash Point: 60.1±21.3 °C, Calc.^*

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

Safety Data

• Hazard Symbols: GHS02
• Risk Statements: H226-H301+H331-H301-H302-H304-H311-H312-H314-H315-H317-H318-H319-H330-H331-H332-H334-H335-H341-H351-H411
• Safety Statements: P203-P210-P233-P240-P241-P242-P243-P260-P261-P262-P264-P264+P265-P270-P271-P272-P273-P280-P284-P301+P316-P301+P317-P301+P330+P331-P302+P352-P302+P361+P354-P303+P361+P353-P304+P340-P305+P351+P338-P305+P354+P338-P316-P317-P318-P319-P320-P321-P330-P331-P332+P317-P333+P317-P337+P317-P342+P316-P361+P364-P362+P364-P363-P370+P378-P391-P403-P403+P233-P403+P235-P405-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Skin sensitization	Skin Sens.	1	H317
Acute toxicity	Acute Tox.	4	H302
Respiratory sensitization	Resp. Sens.	1	H334
Skin corrosion	Skin Corr.	1B	H314
Acute toxicity	Acute Tox.	2	H330
Specific target organ toxicity - single exposure	STOT SE	3	H335
Acute toxicity	Acute Tox.	3	H301
Chronic hazardous to the aquatic environment	Aquatic Chronic	2	H411
Flammable liquids	Flam. Liq.	3	H226
Skin irritation	Skin Irrit.	2	H315
Acute toxicity	Acute Tox.	4	H312
Acute toxicity	Acute Tox.	3	H311
Acute toxicity	Acute Tox.	3	H331
Eye irritation	Eye Irrit.	2	H319
Acute toxicity	Acute Tox.	4	H332
Eye irritation	Eye Irrit.	2A	H319
Aspiration hazard	Asp. Tox.	1	H304
Serious eye damage	Eye Dam.	1	H318
Carcinogenicity	Carc.	2	H351
Germ cell mutagenicity	Muta.	2	H341

Discovery and Applications

trans-4-Methylcyclohexyl isocyanate is an organic compound classified as an isocyanate derivative of a substituted cyclohexane. Its chemical structure comprises a cyclohexane ring with a methyl group in the trans position relative to the isocyanate (-N=C=O) functional group. This molecular arrangement imparts unique reactivity, making it valuable in various industrial and research applications.

The synthesis of trans-4-methylcyclohexyl isocyanate was initially explored as part of efforts to develop specialized isocyanates for polyurethane chemistry. It is typically prepared by the reaction of trans-4-methylcyclohexylamine with phosgene or phosgene substitutes under controlled conditions. Advances in synthetic methods have improved the yield and minimized byproduct formation, making its production more sustainable.

The primary application of trans-4-methylcyclohexyl isocyanate lies in the production of polyurethanes and related polymers. Its reactive isocyanate group readily forms urea and urethane linkages upon reaction with compounds containing hydroxyl or amine groups. This reactivity makes it a critical building block in manufacturing flexible and rigid foams, coatings, adhesives, and elastomers. The trans-methylcyclohexyl moiety contributes to the mechanical strength and thermal stability of the resulting polymers, enhancing their suitability for high-performance applications.

In addition to its industrial uses, trans-4-methylcyclohexyl isocyanate has been employed in the development of specialty chemicals, including agrochemicals and pharmaceuticals. Its structural versatility allows for the creation of derivatives tailored for specific functions, such as bioactive compounds and intermediates for fine chemical synthesis. The compound's unique steric and electronic properties also make it an intriguing subject in organic and materials chemistry research.

Despite its versatility, the handling and use of trans-4-methylcyclohexyl isocyanate require careful safety precautions due to the inherent toxicity and irritant properties of isocyanates. Proper ventilation, personal protective equipment, and adherence to safety guidelines are essential when working with this substance to mitigate risks.

References

2017. An Efficient and Practical Process for the Synthesis of Glimepiride. Synlett, 28(14).
DOI: 10.1055/s-0036-1590836

2012. Synthesis, characterization, and pharmacological evaluation of 1-[2-(6-nitro-4-oxo-2-phenyl-4H-quinazolin-3-yl)-ethyl]-3-phenyl ureas. Medicinal Chemistry Research, 21(9).
DOI: 10.1007/s00044-012-0004-3