Crotonaldehyde is a

chemical compound A chemical compound is a chemical substance composed of many identical molecules (or molecular entities) containing atoms from more than one chemical element held together by chemical bonds. A molecule consisting of atoms of only one element ...

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 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 oil Soybean oil (British English: soyabean oil) is a vegetable oil extracted from the seeds of the soybean (''Glycine max''). It is one of the most widely consumed cooking oils and the second most consumed vegetable oil. As a drying oil, processed so ...

Production and reactivity

Crotonaldehyde is produced by the

aldol condensation An aldol condensation is a condensation reaction in organic chemistry in which two carbonyl moieties (of aldehydes or ketones) react to form a β-hydroxyaldehyde or β-hydroxyketone (an aldol reaction), and this is then followed by dehydration to ...

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 In stereochemistry, prochiral molecules are those that can be converted from achiral to chiral in a single step. An achiral species which can be converted to a chiral in two steps is called proprochiral. If two identical substituents are attach ...

dienophile. It is a

Michael acceptor In organic chemistry, the Michael reaction or Michael addition is a reaction between a Michael donor (an enolate or other nucleophile) and a Michael acceptor (usually an α,β-unsaturated carbonyl) to produce a Michael adduct by creating a carbon ...

. 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 Dimethylamine is an organic compound with the formula (CH3)2NH. This secondary amine is a colorless, flammable gas with an ammonia-like odor. Dimethylamine is commonly encountered commercially as a solution in water at concentrations up to aroun ...

Uses

It is a precursor to fine chemicals.

Sorbic acid Sorbic acid, or 2,4-hexadienoic acid, is a natural organic compound used as a food preservative. It has the chemical formula and the structure . It is a colourless solid that is slightly soluble in water and sublimes readily. It was first isol ...

, a food preservative, and trimethylhydroquinone, a precursor to the

vitamin E Vitamin E is a group of eight fat soluble compounds that include four tocopherols and four tocotrienols. Vitamin E deficiency, which is rare and usually due to an underlying problem with digesting dietary fat rather than from a diet low in vitami ...

, 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 224px, Methylene diurea (MDU) is component of the most popular controlled-release fertilizers. A controlled-release fertiliser (CRF) is a granulated fertiliser that releases nutrients gradually into the soil (i.e., with a controlled release period ...

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