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The Wöhler synthesis is the conversion of ammonium cyanate into urea. This chemical reaction was described in 1828 by Friedrich Wöhler. [1] It is often cited as the starting point of modern organic chemistry. Although the Wöhler reaction concerns the conversion of ammonium cyanate, this salt appears only as an (unstable) intermediate.
Wöhler synthesis of urea by heating ammonium cyanate. The Δ sign indicates the addition of heat. Wöhler's demonstration of urea synthesis has become regarded as a refutation of vitalism, the hypothesis that living things are alive because of some special "vital force". It was the beginning of the end for one popular vitalist hypothesis, the ...
In 1828 Friedrich Wöhler produced the organic chemical urea (carbamide), a constituent of urine, from inorganic starting materials (the salts potassium cyanate and ammonium sulfate), in what is now called the Wöhler synthesis. Although Wöhler himself was cautious about claiming he had disproved vitalism, this was the first time a substance ...
1828 – Friedrich Woehler synthesized urea; first synthesis of an organic compound from inorganic starting materials. 1836 – Theodor Schwann discovered pepsin in extracts from the stomach lining; first isolation of an animal enzyme. 1837 – Theodor Schwann showed that heating air will prevent it from causing putrefaction.
The structure of the molecule of urea is O=C(−NH 2) 2.The urea molecule is planar when in a solid crystal because of sp 2 hybridization of the N orbitals. [8] [9] It is non-planar with C 2 symmetry when in the gas phase [10] or in aqueous solution, [9] with C–N–H and H–N–H bond angles that are intermediate between the trigonal planar angle of 120° and the tetrahedral angle of 109.5°.
Vitalist chemists predicted that organic materials could not be synthesized from inorganic components, but Friedrich Wöhler synthesised urea from inorganic components in 1828. [13] However, contemporary accounts do not support the common belief that vitalism died when Wöhler made urea.
Herman Boerhaave (1668–1738) Dutch chemist, botanist, Christian humanist & physician, first to isolate urea from urine; Kristie Boering (born 1963), American chemist and Earth and planetary scientist; Olga Bogdanova (1896–1982), Soviet chemist; Dale L. Boger (born 1953), American organic and medicinal chemist
The Miller–Urey experiment was a synthesis of small organic molecules in a mixture of simple gases in a thermal gradient created by heating (right) and cooling (left) the mixture at the same time, with electrical discharges.