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CH 2 Cl-CH 2 Cl → CH 2 =CHCl + HCl. The resulting HCl can be reused in oxychlorination reaction. Thermally induced dehydrofluorinations are employed in the production of fluoroolefins and hydrofluoroolefins. One example is the preparation of 1,2,3,3,3-pentafluoropropene from 1,1,2,3,3,3-hexafluoropropane: CF 2 HCH(F)CF 3 → CHF=C(F)CF 3 + HF
Such reactions give alkenes in the case of vicinal alkyl dihalides: [2] R 2 C(X)C(X)R 2 + M → R 2 C=CR 2 + MX 2. Most desirable from the perspective of remediation are dehalogenations by hydrogenolysis, i.e. the replacement of a C−X bond by a C−H bond. Such reactions are amenable to catalysis: R−X + H 2 → R−H + HX
For the second generation reaction starting with the diazoketone, the reaction is performed by irradiation of a 0.7 M solution of the ketone with 1.0-1.2 equivalents of acetylene. A low-pressure mercury-vapor lamp at 254 nm in a photochemical reactor is used for 5–8 hours until all the diazoketone has been consumed as determined by TLC analysis.
Halide-containing compounds are pervasive, making this type of transformation important, e.g. in the production of polymers, drugs. [1] This kind of conversion is in fact so common that a comprehensive overview is challenging. This article mainly deals with halogenation using elemental halogens (F 2, Cl 2, Br 2, I 2). Halides are also commonly ...
A mixture of cis-decalin and CXB can simultaneously match optical index and density of PMMA. [1] Due to the moderate dielectric constant of CXB (ε = 7.9 [ 2 ] ), PMMA acquires charges that can be screened by the addition of salt (e.g. tetrabutyl ammonium bromide ), leading to a very good approximation of colloidal hard sphere . [ 3 ]
Using a carboxylate-to-iodine ratio of 1:1 leads to an alkyl iodide product, in line with Borodin's findings and the modern understanding of the Hunsdiecker reaction. However, a 2:1 ratio favours the formation of an ester product that arises from decarboxylation of one carboxylate and coupling the resulting alkyl chain with the other. [9] [10]
In chemistry, the haloform reaction (also referred to as the Lieben haloform reaction) is a chemical reaction in which a haloform (CHX 3, where X is a halogen) is produced by the exhaustive halogenation of an acetyl group (R−C(=O)CH 3, where R can be either a hydrogen atom, an alkyl or an aryl group), in the presence of a base.
An example of modest stereoselectivity is the dehydrohalogenation of 2-iodobutane which yields 60% trans-2-butene and 20% cis-2-butene. [5] Since alkene geometric isomers are also classified as diastereomers, this reaction would also be called diastereoselective.