Search results
Results from the WOW.Com Content Network
Friedel–Crafts reactions have been used in the synthesis of several triarylmethane and xanthene dyes. [26] Examples are the synthesis of thymolphthalein (a pH indicator) from two equivalents of thymol and phthalic anhydride: A reaction of phthalic anhydride with resorcinol in the presence of zinc chloride gives the fluorophore fluorescein.
Clemmensen reduction conditions are particularly effective at reducing aryl [4]-alkyl ketones, [5] [6] such as those formed in a Friedel-Crafts acylation. The two-step sequence of Friedel-Crafts acylation followed by Clemmensen reduction constitutes a classical strategy for the primary alkylation of arenes .
Phenethyl alcohol is prepared commercially via two routes. Most common is the Friedel-Crafts reaction between benzene and ethylene oxide in the presence of aluminium trichloride. C 6 H 6 + CH 2 CH 2 O + AlCl 3 → C 6 H 5 CH 2 CH 2 OAlCl 2 + HCl. The reaction affords the aluminium alkoxide that is subsequently hydrolyzed to the desired product.
The reaction is a type of Friedel-Crafts acylation with hydrogen chloride and a Lewis acid catalyst. The synthesis of 2,4,6-Trihydroxyacetophenone (THAP) from phloroglucinol is representative: [1] If two-equivalents are added, 2,4-Diacetylphloroglucinol is the product. Hoesch reaction example, 1-(2,4,6-trihydroxyphenyl)ethanone from phloroglucinol
The first step is an amide coupling, while the second step is a Friedel–Crafts reaction. [5] [6] An improved procedure has been developed. [7] [8] See also. Indole;
In addition to the ordinary thermal phenyl ester reaction a photochemical variant is possible. The photo-Fries rearrangement can likewise give [1,3] and [1,5] products, [7] [8] which involves a radical reaction mechanism. This reaction is also possible with deactivating substituents on the aromatic group. Because the yields are low this ...
In the classic example, benzaldehyde is converted to benzoin (PhCH(OH)C(O)Ph). [3] The benzoin condensation was first reported in 1832 by Justus von Liebig and Friedrich Wöhler during their research on bitter almond oil. [4] The catalytic version of the reaction involving cyanide was developed by Nikolay Zinin in the late 1830s. [5] [6 ...
The foot-note lists an abstract for 1,3,5-Tris(aminomethyl)-2,4,6-triethylbenzene, but this is a different molecule, and the abstract doesn't even mention friedel-crafts. I'll fix this later, and add a new section on the limitations of friedel crafts reactions (specifically, polyalkylation, reactivity, and the para/ortho substitution.)