Hantzsch ester refers to an

organic compound Some chemical authorities define an organic compound as a chemical compound that contains a carbon–hydrogen or carbon–carbon bond; others consider an organic compound to be any chemical compound that contains carbon. For example, carbon-co ...

with the formula HN(MeC=C(CO₂Et))₂CH₂ where Me =

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 (whereas normal methane has the formula ). In formulas, the group is often abbreviated as ...

(CH₃) and Et = ethyl (C₂H₅). It is a light yellow solid. The compound is a

1,4-dihydropyridine 1,4-Dihydropyridine (DHP) is an organic compound with the formula CH2(CH=CH)2NH. The parent compound is uncommon, but derivatives of 1,4-dihydropyridine are important commercially and biologically. The pervasive cofactors NADH and NADPH are deriv ...

. It is named after

Arthur Rudolf Hantzsch Arthur Rudolf Hantzsch (7 March 1857 – 14 March 1935) was a German chemist. Life and work Hantzsch studied chemistry in Dresden and graduated at the University of Würzburg under Johannes Wislicenus. As a professor, he taught at the Universitie ...

who described its synthesis in 1881. The compound is a hydride donor, e.g., for reduction of

imine In organic chemistry, an imine ( or ) is a functional group or organic compound containing a carbon–nitrogen double bond (). The nitrogen atom can be attached to a hydrogen or an organic group (R). The carbon atom has two additional single bon ...

s to

amine In chemistry, amines (, ) are organic compounds that contain carbon-nitrogen bonds. Amines are formed when one or more hydrogen atoms in ammonia are replaced by alkyl or aryl groups. The nitrogen atom in an amine possesses a lone pair of elec ...

s. It is a synthetic analogue of

NADH Nicotinamide adenine dinucleotide (NAD) is a coenzyme central to metabolism. Found in all living cells, NAD is called a dinucleotide because it consists of two nucleotides joined through their phosphate groups. One nucleotide contains an ade ...

, a naturally occurring dihydropyridine.

Preparation

Hantzsch ester can be made with a

Hantzsch pyridine synthesis The Hantzsch pyridine synthesis or Hantzsch dihydropyridine synthesis is a multi-component organic reaction between an aldehyde such as formaldehyde Formaldehyde ( , ) (systematic name methanal) is an organic compound with the chemical for ...

where

formaldehyde Formaldehyde ( , ) (systematic name methanal) is an organic compound with the chemical formula and structure , more precisely . The compound is a pungent, colourless gas that polymerises spontaneously into paraformaldehyde. It is stored as ...

, two equivalents of

ethyl acetoacetate The organic compound ethyl acetoacetate (EAA) is the ethyl ester of acetoacetic acid. It is a colorless liquid. It is widely used as a chemical intermediate in the production of a wide variety of compounds. Preparation At large scale, ethyl ac ...

and

ammonium acetate Ammonium acetate, also known as spirit of Mindererus in aqueous solution, is a chemical compound with the formula NH4CH3CO2. It is a white, hygroscopic solid and can be derived from the reaction of ammonia and acetic acid. It is available commerci ...

are combined to afford the product in high yield. Hantzsch pyridine synthesis step 1

Structure

As confirmed by

X-ray crystallography X-ray crystallography is the experimental science of determining the atomic and molecular structure of a crystal, in which the crystalline structure causes a beam of incident X-rays to Diffraction, diffract in specific directions. By measuring th ...

, Hantzsch ester has a planar C₅N core.

References

{{Reflist Dihydropyridines Substances discovered in the 19th century

Preparation

Structure

Further reading

See also

References