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Names
IUPAC name 2-vinylpyridine
Other names 2VP
Identifiers
Properties
Chemical formula	C7H7N
Molar mass	105.14 g·mol−1
Appearance	brown, clear liquid
Density	.977 g/cm³
Melting point	-50 °C
Boiling point	158 °C
Solubility in water	27.5 g/L
Vapor pressure	96 hPa (72 mmHg) at 100 °C
Acidity (pKa)	4.98
Viscosity	1.17 mPas
Hazards
Flash point	48 °C
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). N verify (what is YN ?) Infobox references

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2-Vinylpyridine, first synthesized in 1887, is a polymer precursor used as a copolymer for textiles and adhesives.

Synthesis

It is synthesized by treatment of 2-methylpyridine with aqueous formaldehyde, followed by dehydration of the resulting intermediate alcohol. The reaction is carried out between 150 – 200 ̊C in an autoclave. The conversion must be kept relatively low with short reaction time to suppress the formation of byproducts. After removal of unreacted 2-methylpyridine by distillation, concentrated aqueous sodium hydroxide is added to the residue and the resultant mixture is distilled under reduced pressure. During distillation, the dehydration of 2-(2-pyridyl)ethanol occurs to give 2-vinylpyridine as a distillate, which can be purified further by fractional distillation under reduced pressure in the presence of an inhibitor such as 4-tert-butylcatecohol. Synthesis is also possible by reaction with acrylonitrile and acetylene reacting in the presence of cyclopentadienylcobalt – cycloocta-1,5-diene catalyst to give 2-vinylpyridine with 93% selectivity. The 2-vinylpyridine synthesis must be carried out in pure acrylonitrile below 130–140 ̊C, otherwise acrylonitrile and the product 2-vinylpyridine undergo thermal polymerization.

Properties

2-vinylpyridine is a brown liquid. It is unstable as it is sensitive to polymerization. It may be stabilized with a free radical eliminator such as tert-butylcatechol. Due to the electron-withdrawing effect of the ring nitrogen atom, 2-vinylpyridine acts as an electrophile. Nucleophiles such as methoxide, cyanide, hydrogen sulfide, and others add to 2-vinylpyridine at the vinylic site to give addition products. As 2-vinylpyridine is heat sensitive, long term storage should maintain a temperature between 3-4 C. Incompatible with strong oxidizing agents, strong bases, strong acids.

Uses

Medical

The addition product of methanol to 2- vinylpyridine, 2-(2 methoxyethyl)pyridine is a veterinary anthelmintic.

Catalyst

Reacting 2-vinylpyridine with 4-pyridinecarbonitrile and HCl, the reaction will give 1-[2-(2-Pyridyl)ethyl]-4- cyanopyridinium chloride which then can be used to make N,N-dimethyl-4-pyridinamine. This product’s major uses are as a catalyst for acylation, alkylation, halogenation, cyanation, and silylation, and as an accelerator in the manufacture of polyurethanes.

Polymerization

2-vinylpyridine is readily polymerized or copolymerized with styrene, butadiene, isobutylene, methyl methacrylate, and other compounds in the presence of radical, cationic, and anionic initiators. The homopolymer is soluble in organic solvents such as methanol and acetone, whereas cross-linked copolymers are insoluble in organic solvents.

Adhesive

The most common application of 2-vinylpyridine is for use in the production of a latex terpolymer of 2-vinylpyridine, styrene, and butadiene, used as a tire-cord binder. The tire cord is treated first with a resorcinol-formaldehyde polymer and then with a terpolymer made from 15% 2-vinylpyridine, styrene, and butadiene. This treatment gives the close bonding of tire cord to rubber essential in the production of tires.

Textiles

2-Vinylpyridine is an additive in dying processes for acrylic fibers: 1–5% of copolymerized 2-vinylpyridine provide the reactive sites for the dye.