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Tris(pentafluorophenyl)borane, sometimes referred to as "BCF", is the chemical compound (C 6 F 5) 3 B.It is a white, volatile solid. The molecule consists of three pentafluorophenyl groups attached in a "paddle-wheel" manner to a central boron atom; the BC 3 core is planar.
In chemistry, isomerization or isomerisation is the process in which a molecule, polyatomic ion or molecular fragment is transformed into an isomer with a different chemical structure. [1] Enolization is an example of isomerization, as is tautomerization .
[10] [11] Dienyl esters such as 11 were transformed into substituted bicyclo[2.2.2]octanes via an isomerization step stabilized by a hemiacetal azolium intermediate (13). [11] The activation barrier of isomerization of 1,3–hexadiene through a [1,5]–shift is 41 Kcal mol–1 and is expected to increase with conjugation to the ester, thus ...
Moderately high temperatures, above 70 °C, increase the yield of fructose by at least half in the isomerization step. [26] The enzyme requires a divalent cation such as Co 2+ and Mg 2+ for peak activity, an additional cost to manufacturers. Glucose isomerase also has a much higher affinity for xylose than for glucose, necessitating a carefully ...
In the third step, an isomerization step protonates the nitrogen atom leading to the amide. The Beckmann rearrangement mechanism The same computation with a hydroxonium ion and 6 molecules of water has the same result, but when the migrating substituent is a phenyl group, the mechanism favors the formation of an intermediate three-membered π ...
The gauche effect is very sensitive to solvent effects, due to the large difference in polarity between the two conformers.For example, 2,3-dinitro-2,3-dimethylbutane, which in the solid state exists only in the gauche conformation, prefers the gauche conformer in benzene solution by a ratio of 79:21, but in carbon tetrachloride, it prefers the anti conformer by a ratio of 58:42. [9]
UOP Penex process [3] During isomerisation, the low-octane normal hydrocarbons are converted into their higher-octane isomers. For this purpose, the feed material is passed over a fixed bed catalyst in the presence of hydrogen. The hydrogen is continuously circulated in the reactor circuit. [5]
The alkyne zipper reaction is an organic reaction that involves isomerization of a non terminal alkyne into a terminal alkyne. This reaction was first reported by Alexey Favorsky in 1887 (J. Russ. Phys.-Chem. Soc., 19, 414 (1887)).