Methyl vinyl ketone

• Butenone
• 1-butene -3-one
• But-3 -en- 2-one ( IUPAC)
• Vinyl methyl

Light-sensitive, volatile, colorless liquid with a pungent odor

Liquid

0.83 g · cm -3

-7 ° C

81.4 ° C

100 hPa ( 20 ° C)

Miscible with water

1.4081 (20 ° C)

Risk

23.1 mg · kg -1 ( LD50, rat, oral)

Template: Infobox chemical / molecular formula search available

Methyl vinyl ketone, is the simplest unsaturated ketone, a pungent-smelling liquid that readily polymerized.

Production and representation

The compound can be prepared in the presence of sulfuric acid and mercury (II ) sulfate by hydration of vinyl acetylene ( butenyne ):

Properties

Methyl vinyl ketone is a colorless light-sensitive liquid, boiling at atmospheric pressure at 81 ° C. The compound is less than 28 ° C, completely miscible with water. Above this temperature, there exists a miscibility gap in the range between about 10 and 40 mole percent.

Use

Methyl vinyl ketone is used to prepare gas-impermeable plastics and as an intermediate in the production of drugs, fungicides, and other chemical compounds (e.g., 2 -ethoxy- buta -1 ,3-diene or 1-phenyl -pentan- 1 ,4-dione ). It is thereby converted, for example, by a Diels -Alder reaction or Robinson annulation.

Safety

Methyl vinyl ketone tends to form explosive peroxides and spontaneous polymerization, which can already be triggered by sunlight. The vapors of butenone form explosive mixtures with air. The compound has a flash point of -7 ° C. The explosion range is between 2.1 vol% as the lower explosive limit ( LEL) and 15.6 vol% as the upper explosive limit ( UEL). The ignition temperature is 491 ° C. The fabric falls within the temperature class T1.