Crotonaldehyde is a chemical compound with the

formula In science, a formula is a concise way of expressing information symbolically, as in a mathematical formula or a ''chemical formula''. The informal use of the term ''formula'' in science refers to the general construct of a relationship betwee ...

CH₃CH=CHCHO. The compound is usually sold as a mixture of the ''E''- and ''Z''-isomers, which differ with respect to the relative position of the

methyl In organic chemistry, a methyl group is an alkyl derived from methane, containing one carbon atom bonded to three hydrogen atoms, having chemical formula . In formulas, the group is often abbreviated as Me. This hydrocarbon group occurs in many ...

and formyl groups. The ''E''-isomer is more common (data given in Table is for the ''E''-isomer). This

lachrymatory Lachrymatory or lacrymatory may refer to: * Something that has the effect of ''lachrymation'', causing the secretion of tears * Tear gas Tear gas, also known as a lachrymator agent or lachrymator (), sometimes colloquially known as "mace" af ...

liquid is moderately soluble in water and miscible in organic solvents. As an unsaturated aldehyde, crotonaldehyde is a versatile intermediate in

organic synthesis Organic synthesis is a special branch of chemical synthesis and is concerned with the intentional construction of organic compounds. Organic molecules are often more complex than inorganic compounds, and their synthesis has developed into one o ...

. It occurs in a variety of foodstuffs, e.g. soybean oils.

Production and reactivity

Crotonaldehyde is produced by the aldol condensation of

acetaldehyde Acetaldehyde (IUPAC systematic name ethanal) is an organic chemical compound with the formula CH3 CHO, sometimes abbreviated by chemists as MeCHO (Me = methyl). It is a colorless liquid or gas, boiling near room temperature. It is one of the mos ...

: :2 CH₃CHO → CH₃CH=CHCHO + H₂O Crotonaldehyde is a multifunctional molecule that exhibits diverse reactivity. It is a prochiral dienophile. It is a Michael acceptor. Addition of

methylmagnesium chloride Methylmagnesium chloride is an organometallic compound with the general formula CH3MgCl. This highly flammable, colorless, and moisture sensitive material is the simplest Grignard reagent and is commercially available, usually as a solution in te ...

produces 3-penten-2-ol. Polyurethane catalyst ''N'',''N'',''N''′,''N''′-tetramethyl-1,4-butanediamine (also known as NIAX TMBDA) was obtained by hydrogenating the reaction product of crotonaldehyde and dimethylamine.

Uses

It is a precursor to fine chemicals. Sorbic acid, a food preservative, and trimethylhydroquinone, a precursor to the vitamin E, are prepared from crotonaldehyde. Other derivatives include crotonic acid and 3-methoxybutanol. It adds two equivalents of urea to give the

pyrimidine Pyrimidine (; ) is an aromatic, heterocyclic, organic compound similar to pyridine (). One of the three diazines (six-membered heterocyclics with two nitrogen atoms in the ring), it has nitrogen atoms at positions 1 and 3 in the ring. The other ...

derivative that is employed as a controlled-release fertilizer.

Safety

Crotonaldehyde is a potent irritant even at the ppm levels. It is not very toxic, with an of 174 mg/kg (rats, oral).

References

External links

Hazardous Substance Fact Sheet

{{Authority control Alkenals Lachrymatory agents Hazardous materials

Production and reactivity

Uses

Safety

See also

References

External links