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Furan fatty acids are a group of fatty acids that contain a furan ring. To this furan ring, an unbranched carboxylic acid and, at another position, an alkyl residue are attached. Natural furan fatty acids are mono- or di-methylated on the furan ring. [1] Furan fatty acids can be found in a variety of plant and animal species.
The isostere concept was formulated by Irving Langmuir in 1919, [3] and later modified by Grimm. Hans Erlenmeyer extended the concept to biological systems in 1932. [ 4 ] [ 5 ] [ 6 ] Classical isosteres are defined as being atoms, ions and molecules that had identical outer shells of electrons, This definition has now been broadened to include ...
The name "furan" comes from the Latin furfur, which means bran [5] (furfural is produced from bran). The first furan derivative to be described was 2-furoic acid, by Carl Wilhelm Scheele in 1780. Another important derivative, furfural, was reported by Johann Wolfgang Döbereiner in 1831 and characterised nine years later by John Stenhouse.
Unlike furan and thiophene, it has a dipole in which the positive end lies on the side of the heteroatom, with a dipole moment of 1.58 D. In CDCl 3, it has chemical shifts at 6.68 (H2, H5) and 6.22 (H3, H4). Pyrrole is an extremely weak base for an amine, with a conjugate acid pK a of −3.8.
Furfural is used to make other furan derivatives, such as furoic acid, via oxidation, [30] and furan itself via palladium catalyzed vapor phase decarbonylation. [ 4 ] There is a good market for value added chemicals that can be obtained from furfural.
2-Furoic acid is an organic compound, consisting of a furan ring and a carboxylic acid side-group. Along with other furans, its name is derived from the Latin word furfur , meaning bran, from which these compounds were first produced. [ 2 ]
Bromous acid is a product of the Belousov–Zhabotinsky reaction resulting from the combination of potassium bromate, cerium(IV) sulfate, propanedioic acid and citric acid in dilute sulfuric acid. Bromous acid is an intermediate stage of the reaction between bromate ion (BrO − 3) and bromine (Br −): [5] [6] BrO − 3 + 2 Br − → HBrO 2 ...
Bond energies to bromine tend to be lower than those to chlorine but higher than those to iodine, and bromine is a weaker oxidising agent than chlorine but a stronger one than iodine. This can be seen from the standard electrode potentials of the X 2 /X − couples (F, +2.866 V; Cl, +1.395 V; Br, +1.087 V; I, +0.615 V; At, approximately +0.3 V).