Synthesis from 2- phenol

Senzopyranone synthesis from phenols and ketoesters or unsaturated acids... 

The anethole ring has two functional groups - an ether and a hydrocarbon side chain with a double bond. The ether is synthesized first - by a Williamson ether synthesis from phenol and CH3I. The hydrocarbon side chain results from a Friedel-Crafts acylation of the ether. Reduction of the ketone, bromination and dehydrohalogenation are used to introduce the double bond. 

Coumarin synthesis from phenols and ethyl acetoacetate. ... 

The structure elucidation of salicylic acid we owe to Hermann Kolbe (1818-1884) and Victor Meyer (1848-1897). Also its industrial synthesis, from phenol and carbon dioxide, can be traced back to Kolbe, who developed this process in 1874. Previously, salicylic acid was produced by hydrolysis of its methyl ester, which in turn was obtained from wintergreen oU, a product of the steam distillation ofthe leaves ofthe American wintergreen oiteaheiry (Gaultheria procutn-bens) and the spice birch (Betula lento). 

Phenol is the starting material for the synthesis of 2,3,4,5,6-pentachlorophenol, known alternatively as pentachlorophenol, or more simply as penta. At one time, penta was widely used as a wood preservative for decks, siding, and outdoor wood furniture. Draw the structural formula for pentachlorophenol and describe its synthesis from phenol. 

S I M O N I S Benzopyrone Synthesis Benzopyrene synthesis from phenols and p-ketoesters. 

The substantial drawback of BPA synthesis from phenol and acetone is the formation of more than 30 various b3q>roducts in the side reactions occurring during the process (Figure 7.9) [53,54]. These are mainly the isomers of BPA, i.e., the o,p-isomers of BPA, the Dianin s compound, chromans, trisphenols and polyphenols as shown in Figure 7.10. 

Figure 7.10 Chemical structure of the main side products of BPA synthesis from phenol and acetone.

SCHEME 5.4 Diphenyl carbonate synthesis from phenol and CO. ... 

The most important synthesis of phenols m the laboratory is from amines by hydrolysis of their corresponding diazonmm salts as described m Section 22 17... 

As improvements over P-methylumbeUiferone (55—57), 4-methyl-7-amino-coumarin [26093-31-2] (12a) and 7-dimethylamino-4-methylcoumarin [87-014] (12b) (58—61) were proposed. These compounds are used for brightening wool and nylon either in soap powders or detergents, or as salts under acid dyeing conditions. They are obtained by the Pechmaim synthesis from appropriately substituted phenols and P-ketocarboxyflc acid esters or nitriles in the presence of Lewis acid catalysts (see Coumarin). 

The synthesis of chlorarul [118-75-2] (20) has been improved. The old processes starting from phenol or 2,4,6-trichlorophenol have been replaced by new ones involving hydroquinone chlorination. These processes allow the preparation of chlorarul of higher purity, avoiding traces of pentachlorophenol. Different types of chlorination conditions have been disclosed. The reaction can be performed according to the following stoichiometry, operating with chlorine in aqueous acetic acid (86,87), biphasic medium (88), or in the presence of surfactants (89). 

Catechol is produced by coproduction with hydroquinone starting from phenol. Other techniques such as coal extraction remain marginal. The installed capacities (- 25,000 t/yr) are now sufficient to cover the demand. Catechol is mainly used for synthesis in food, pharmaceutical, or agrochemical ingredients. A specific appHcation of / fZ-butylcatechol is as a polymerisation inhibitor. 

Fig. 1. Catalytic cycle for synthesis of bisphenol A from phenol and acetone in the presence of a dissociated mineral acid (10).

ZINCKE - SUHL Cyclohexadienone synthesis Synthesis of cyclohexadienones from phenols by Fnedel Crafts alkylafion... 

By far the preponderance of the 3400 kt of current worldwide phenolic resin production is in the form of phenol-formaldehyde (PF) reaction products. Phenol and formaldehyde are currently two of the most available monomers on earth. About 6000 kt of phenol and 10,000 kt of formaldehyde (100% basis) were produced in 1998 [55,56]. The organic raw materials for synthesis of phenol and formaldehyde are cumene (derived from benzene and propylene) and methanol, respectively. These materials are, in turn, obtained from petroleum and natural gas at relatively low cost ([57], pp. 10-26 [58], pp. 1-30). Cost is one of the most important advantages of phenolics in most applications. It is critical to the acceptance of phenolics for wood panel manufacture. With the exception of urea-formaldehyde resins, PF resins are the lowest cost thermosetting resins available. In addition to its synthesis from low cost monomers, phenolic resin costs are often further reduced by extension with fillers such as clays, chalk, rags, wood flours, nutshell flours, grain flours, starches, lignins, tannins, and various other low eost materials. Often these fillers and extenders improve the performance of the phenolic for a particular use while reducing cost. 

The key compound in the synthesis of aspir in, salicylic acid, is prepared from phenol by a process discovered in the nineteenth century by the German chemist Hermann Kolbe. In the Kolbe synthesis, also known as the Kolbe—Schmitt reaction, sodium phen-oxide is heated with carbon dioxide under pressure, and the reaction mixture is subsequently acidified to yield salicylic acid ... 

It IS by a similar process that alizaiin has been synthesised w ith the oliject of ascertaining its constitution (see Notes on Prep. 110, p. 316), When two molecules of phenol and one molecule of phthalic anhydride are heated together with cone, sulphuric acid, then phenolphthalein is formed (Baeyei). Its constitution has been determined by its synthesis from phthalyl chloride and benzene by means of the Friedel-Crafts leaction (see Notes on Piep. 100, p. 309). Phthalyl chloride and benzene yield in presence of AlCl., phthalophenone. 

Phenol was manufactured for many years by the Dow process, in which chlorobenzene reacts with NaOH at high temperature and pressure (Section 16.S). Now, however, an alternative synthesis from isopropylbenzene, commonly called... 

Propose a synthesis of diethylstilbestrol (Problem 2/.44) from phenol and any other organic compound required. 

Iron impregnated on activated carbon was used as catalyst for the direct synthesis of phenol from benzene. The effect of Sn addition to the catalyst was studied. The prepared catalysts were characterized by BET, SEM and XRD analysis. The catalyst 5.0Fe/AC showed good activity in the conversion of benzene and addition of Sn seemed to improve the selectivity of phenol in the reaction. 

Fluoran compound used as leuco dye needs to have substituent(s) on the xanthene moiety to develop color, though fluoran 1 itself is prepared as a by-product in the synthesis of phenolphthalein from phenol and phthalic anhydride. 

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