Isobutyraldehyde is the

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 (CH₃)₂CHCHO. It is an

aldehyde In organic chemistry, an aldehyde () is an organic compound containing a functional group with the structure . The functional group itself (without the "R" side chain) can be referred to as an aldehyde but can also be classified as a formyl grou ...

, isomeric with n-butyraldehyde (butanal). Isobutyraldehyde is made, often as a side-product, by the

hydroformylation Hydroformylation, also known as oxo synthesis or oxo process, is an industrial process for the production of aldehydes from alkenes. This chemical reaction entails the net addition of a formyl group (CHO) and a hydrogen atom to a carbon-carbon d ...

propene Propylene, also known as propene, is an unsaturated organic compound with the chemical formula CH3CH=CH2. It has one double bond, and is the second simplest member of the alkene class of hydrocarbons. It is a colorless gas with a faint petro ...

. Its odour is described as that of wet cereal or straw. It undergoes the

Cannizaro reaction The Cannizzaro reaction, named after its discoverer Stanislao Cannizzaro, is a chemical reaction which involves the base-induced disproportionation of two molecules of a non-enolizable aldehyde to give a primary alcohol and a carboxylic acid. ...

even though it has alpha hydrogen atom. It is a colorless volatile liquid.

Synthesis

Isobutyraldehyde is produced industrially by the hydroformylation of propene. Several million tons are produced annually.Boy Cornils, Richard W. Fischer, Christian Kohlpaintner "Butanals" in Ullmann's Encyclopedia of Industrial Chemistry, 2000, Wiley-VCH, Weinheim.

Biological routes

In the context of

butanol fuel 220px, Butanol, a C-4 hydrocarbon is a promising bio-derived fuel, which shares many properties with gasoline. Butanol may be used as a fuel in an internal combustion engine. It is more similar to gasoline than it is to ethanol. A C4-hydrocarbon ...

, isobutyraldehyde is of interest as a precursor to

isobutanol Isobutanol (IUPAC nomenclature: 2-methylpropan-1-ol) is an organic compound with the formula (CH3)2CHCH2OH (sometimes represented as ''i''-BuOH). This colorless, flammable liquid with a characteristic smell is mainly used as a solvent either dire ...

. ''E. coli'' as well as several other organisms has been genetically modified to produce isobutanol. α-

Ketoisovalerate α-Ketoisovaleric acid is an organic compound with the formula (CH3)2CHC(O)CO2H. It is a ketoacid. With a melting point just above room temperature, it is usually an oil or semi-solid. The compound is colorless. It is a metabolite of valine an ...

, derived from oxidative deamination of

valine Valine (symbol Val or V) is an α-amino acid that is used in the biosynthesis of proteins. It contains an α- amino group (which is in the protonated −NH3+ form under biological conditions), an α- carboxylic acid group (which is in the deprotona ...

, is prone to decarboxylation to give isobutyraldehyde, which is susceptible to reduction to the alcohol: :(CH₃)₂CHC(O)CO₂H → (CH₃)₂CHCHO + CO₂ :(CH₃)₂CHCHO + NADH + H⁺ → (CH₃)₂CHCH₂OH + NAD⁺

Other routes

It can also be produced using engineered bacteria. Strong mineral acids catalyse the rearrangement of methallyl alcohol to isobutyraldehyde.

Reactions

Hydrogenation Hydrogenation is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst such as nickel, palladium or platinum. The process is commonly employed to reduce or saturate organ ...

of the aldehyde gives

Oxidation Redox (reduction–oxidation, , ) is a type of chemical reaction in which the oxidation states of substrate change. Oxidation is the loss of electrons or an increase in the oxidation state, while reduction is the gain of electrons or a ...

gives

methacrolein Methacrolein, or methacrylaldehyde, is an unsaturated aldehyde. It is a clear, colorless, flammable liquid. Methacrolein is one of two major products resulting from the reaction of isoprene with OH in the atmosphere, the other product being ...

methacrylic acid Methacrylic acid, abbreviated MAA, is an organic compound. This colorless, viscous liquid is a carboxylic acid with an acrid unpleasant odor. It is soluble in warm water and miscible with most organic solvents. Methacrylic acid is produced indu ...

. Condensation with

formaldehyde Formaldehyde ( , ) (systematic name methanal) is a naturally occurring organic compound with the formula and structure . The pure compound is a pungent, colourless gas that polymerises spontaneously into paraformaldehyde (refer to section ...

gives

hydroxypivaldehyde Hydroxypivaldehyde is the organic compound with the formula HOCH2(CH3)2CCHO. A colorless liquid, it is produced by condensation of formaldehyde and isobutyraldehyde: :CH2O + (CH3)2CHCHO → HOCH2(CH3)2CCHO The compound is a rare example of a ...

References

{{reflist Flavors Aldehydes