The Volhard–Erdmann cyclization is an

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 ...

of alkyl and aryl

thiophene Thiophene is a heterocyclic compound with the formula C4H4S. Consisting of a planar five-membered ring, it is aromatic as indicated by its extensive substitution reactions. It is a colorless liquid with a benzene-like odor. In most of its react ...

s by cyclization of disodium

succinate Succinic acid () is a dicarboxylic acid with the chemical formula (CH2)2(CO2H)2. The name derives from Latin ''succinum'', meaning amber. In living organisms, succinic acid takes the form of an anion, succinate, which has multiple biological ro ...

or other 1,4-difunctional compounds (γ-oxo acids, 1,4-diketones, chloroacetyl-substituted esters) with

phosphorus heptasulfide Phosphorus is a chemical element with the symbol P and atomic number 15. Elemental phosphorus exists in two major forms, white phosphorus and red phosphorus, but because it is highly reactive, phosphorus is never found as a free element on ...

. The reaction is named after

Jacob Volhard Jacob Volhard (4 June 1834 – 14 January 1910) was the German chemist who discovered, together with his student Hugo Erdmann, the Volhard–Erdmann cyclization reaction. He was also responsible for the improvement of the Hell–Volhard–Zel ...

and

Hugo Erdmann Hugo Wilhelm Traugott Erdmann (8 May 1862 – 25 June 1910) was the German chemist who discovered, together with his doctoral advisor Jacob Volhard, the Volhard-Erdmann cyclization. In 1898 he was the first who coined the term ''noble gas'' (the ...

. An example is the synthesis of 3-methylthiophene starting from

itaconic acid Itaconic acid, or methylidenesuccinic acid, is an organic compound. This dicarboxylic acid is a white solid that is soluble in water, ethanol, and acetone. Historically, itaconic acid was obtained by the distillation of citric acid, but currently ...

: :

References

{{DEFAULTSORT:Volhard-Erdmann cyclization Sulfur heterocycle forming reactions Name reactions