2,2-Dimethyl-1,3-propanediol
[CAS# 126-30-7]

Identification

• Classification: Organic raw materials >> Alcohols, phenols, phenolic compounds and derivatives >> Acyclic alcohol
• Name: 2,2-Dimethyl-1,3-propanediol
• Synonyms: Neopentyl glycol
• Molecular Formula: C₅H₁₂O₂
• Molecular Weight: 104.15
• CAS Registry Number: 126-30-7
• EC Number: 204-781-0
• SMILES: CC(C)(CO)CO

Properties

• Density: 1.06
• Melting point: 122-128 ºC
• Boiling point: 208 ºC
• Flash point: 107 ºC
• Water solubility: 830 g/L (20 ºC)

Safety Data

• Hazard Symbols: GHS05;GHS07 Danger
• Hazard Statements: H315-H318-H319
• Precautionary Statements: P264-P264+P265-P280-P302+P352-P305+P351+P338-P305+P354+P338-P317-P321-P332+P317-P337+P317-P362+P364

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Serious eye damage	Eye Dam.	1	H318
Eye irritation	Eye Irrit.	2	H319
Skin irritation	Skin Irrit.	2	H315
Specific target organ toxicity - single exposure	STOT SE	3	H335

Discovory and Applicatios

2,2-Dimethyl-1,3-propanediol, also known as neopentyl glycol (NPG), is an organic compound with the chemical formula C5H12O2. This diol was first synthesized in the early 20th century by German chemists Alexander von Baeyer and Adolf Wurtz while studying alcohols and their derivatives. The synthesis of NPG involves the aldol reaction of isobutyraldehyde with formaldehyde followed by hydrogenation. Its unique structure, characterized by a quaternary carbon atom bonded to two hydroxyl groups, gives it unique chemical and physical properties.

NPG is a white crystalline solid with a melting point of 124-128°C and a boiling point of 208°C. It is soluble in water, alcohols, and many organic solvents. The two hydroxyl groups and the highly branched structure contribute to its stability and resistance to oxidative and thermal degradation.

NPG is widely used in the production of polyesters and resins. It is a key ingredient in alkyd resins, which are used in coatings, paints, and varnishes. NPG enhances the durability, gloss and weatherability of these products, making them suitable for industrial and consumer applications. In unsaturated polyester resins, NPG helps improve mechanical properties, chemical resistance and heat resistance. These resins are used in automotive parts, building materials and marine applications.

NPG is used as a plasticizer. In PVC formulations, NPG-based plasticizers provide flexibility, durability and resistance to oil and solvent extraction. This makes PVC products more versatile and durable for applications such as cables, flooring and medical devices. NPG is also used in the production of polyurethane foams and elastomers, enhancing their flexibility and elasticity.

NPG has a wide range of applications in the pharmaceutical and cosmetic industries. In pharmaceuticals, NPG is used as a stabilizer and excipient to improve the solubility and stability of active ingredients. It is used in cosmetics and personal care products for its moisturizing properties, which enhance the stability and texture of the formulation.

NPG is used in the production of lubricants and additives. It is a key ingredient in synthetic lubricants, helping to improve thermal stability, oxidation resistance and low volatility. These lubricants are used in high-performance engines and machinery. NPG is used in fuel and oil additives to improve engine performance and life by reducing deposits and wear.

NPG is an important chemical intermediate. It is used in the production of various esters and ethers, which are used as intermediates in the synthesis of solvents, plasticizers, and other chemicals. NPG is a precursor to the production of polyols for polyurethane foams, adhesives, and sealants, helping to improve mechanical properties and stability.

NPG is considered to be less toxic, but proper safety measures should still be followed and gloves, goggles, and protective clothing should be worn to prevent skin and eye contact. Adequate ventilation is required to avoid inhalation of dust or vapors. It should be stored in a cool, dry place away from sources of ignition and incompatible materials such as strong oxidants.

NPG is biodegradable and has relatively low environmental impact if managed properly. It can be broken down by microorganisms in the environment, which reduces the potential for its long-term environmental persistence. Measures should be taken to prevent large-scale discharges into waterways, as high concentrations can be harmful to aquatic life.

References

1959. Polyol-Based Urethane Foams Using Neopentyl Glycol. Industrial & Engineering Chemistry, 51(12).
DOI: 10.1021/ie50600a035

2024. Fabrication of Cu-based catalysts for the synthesis of neopentyl glycol. Catalysis Today, 426.
DOI: 10.1016/j.cattod.2023.114387

2024. Neopentyl Glycol-Based Radiotracers for Prostate Cancer Imaging. Journal of Nuclear Medicine, 65(4).
DOI: 10.2967/jnumed.123.266123