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Synthesis of acetone and phenol

Cumene is prepared on a large scale from benzene and propylene as an intermediate in the synthesis of acetone and phenol. This makes it an inexpensive and readily available starting material for the production of Galaxolide . Three further electrophilic addition reactions complete the synthesis. Firstly, isoamylene is added, to form pentamethylindane, to which propylene oxide is added. Finally, treatment with formaldehyde leads, via the hemiacetal, to the isochroman. [Pg.95]

A brief screen of potential radical mediators revealed that most oxidants facilitated the tosyl group elimination (Table 4). However, two lead reagents were identified, azobisisobutyronitrile (AIBN) and cumene hydroperoxide (CHP), both of which delivered the product in >80% solution yield, while minimizing over-oxidation. Ultimately, CHP was selected due to its commercial availability and ease of handling—CHP is used in the commercial synthesis of acetone and phenol (via the Hock rearrangement)." ... [Pg.219]

The following reaction is the first step in the industrial synthesis of acetone and phenol (CeHsOH). AIBN (2.2 -azobisisobutyroni-trile) initiates radical reactions by breaking down upon heating to form two isobutyronitrile radicals and nitrogen gas. Using an isobu-tyronitrile radical to initiate the reaction, write a mechanism for the following process. [Pg.495]

As it was mentioned earlier, many byproducts are formed in the conventional BPA synthesis from acetone and phenol that unfavorably results in the necessity of very costly purification steps and loss of the raw materials. Thus, recently the method of BPA... [Pg.246]

PROPENE The major use of propene is in the produc tion of polypropylene Two other propene derived organic chemicals acrylonitrile and propylene oxide are also starting materials for polymer synthesis Acrylonitrile is used to make acrylic fibers (see Table 6 5) and propylene oxide is one component in the preparation of polyurethane polymers Cumene itself has no direct uses but rather serves as the starting material in a process that yields two valuable indus trial chemicals acetone and phenol... [Pg.269]

In a related approach from the same laboratory, the perfluorooctylsulfonyl tag was employed in a traceless strategy for the deoxygenation of phenols (Scheme 7.82) [94], These reactions were carried out in a toluene/acetone/water (4 4 1) solvent mixture, utilizing 5 equivalents of formic acid and potassium carbonate/[l,T-bis(diphe-nylphosphino)ferrocene]dichloropalladium(II) [Pd(dppf)Cl2] as the catalytic system. After 20 min of irradiation, the reaction mixture was subjected to fluorous solid-phase extraction (F-S PE) to afford the desired products in high yields. This new traceless fluorous tag has also been employed in the synthesis of pyrimidines and hydantoins. [Pg.352]

We have found several examples in which adjacent cationic charge centers are shown to activate carboxonium electrophiles. A convenient method for studying this activation is through the use of the hydroxyalkylation reaction, a commercially important, acid-catalyzed condensation of aldehydes and ketones with arenes.10 It is used for example in the synthesis of bis-phenol A from acetone and phenol (eq 6). While protonated acetone is able to react with activated arenes like phenol, it is not capable of reacting with less nucleophilic... [Pg.161]

Bisphenol A is manufactured by a reaction between phenol and acetone, the two products from the cumene hydroperoxide rearrangement. Bisphenol A is an important diol monomer used in the synthesis of polycarbonates and epoxy resins. [Pg.17]

Catalysis (27-30) which allows for the direct oxidation of benzene to produce phenol. Economic analyses have shown that these are attractive only in specific instances where, for example, a cheap source of N20 is available. Nevertheless, these developments have shown that direct oxidation is possible and further innovations in this area should probably be expected. The demands for acetone and phenol have generally tended to follow each other. However, as bisphenol A becomes an even more important end use for phenol and acetone, there will be a need for a separate source of phenol. The synthesis of bisphenol A requires two moles of phenol for every one mole of acetone, while the peroxidation of cumene produces one mole of each. Still, processes such as the direct oxidation of benzene are unlikely to have a major impact on cumene demand in the short term since there are competing processes such as Mitsui s for converting acetone back to propylene. [Pg.236]

The first totally synthetic route to a solvent in the United States was the synthesis of isopropyl alcohol from propylene by Melco Chemical Corporation in 1917. In 1928 Union Carbide made acetone from isopropyl alcohol the synthesis of acetone in the cumene-to-phenol process came much later and now is the source of about 85% of acetone production. In 1927 Du Pont began the synthesis of methanol. Synthetic ethyl alcohol was made from ethylene by Union Carbide in 1929. Specialized books on ethyl alcohol (14. 15) and isopropyl alcohol (16) give many details on the manufacture, properties, and uses of these major products. [Pg.666]

About 15.3 million metric tons (16.8 million short tons) of propylene were produced for commercial sale in the United States in 2004. About 39 percent of that amount was used for the production of polypropylene. Almost all of the remaining production was also used for the synthesis of chemical compounds, especially acrylonitrile (14 percent), propylene oxide (11 percent), cumene (10 percent), oxo alcohols (8 percent), isopropyl alcohol (7 percent), oligomers (5 percent) and acrylic acid (3 percent). Acrylonitrile, propylene oxide, oxo alcohols, and acrylic acids are all used primarily for the production of various types of polymers. Cumene is itself used as a raw material in the production of other organic compounds, especially acetone and phenol. [Pg.671]

Boron, Phosphorus, and Selenium Compounds. Oxone has been used to oxidize carbon-boron bonds during the work-up of hydroboration reactions to obtain high yields of the resultant alcohols (eq 73). Aqueous Oxone/acetone oxidizes electron-poor and electron-rich aromatic and aliphatic boronic acids and esters to the corresponding alcohols rapidly and efficiently (eq 74). A one-pot procedure for the synthesis of iweta-substituted phenols from benzenes has been developed, and a similar strategy has been devised for the synthesis of Boc-oxindoles from Boc-indoles. i3i... [Pg.342]

As we saw in Section 6.3, treatment of an alkene with a strong acid, most commonly FIX, H2SO4, H3PO4, or HF/BFj, generates a carbocation. Cumene, an intermediate in the industrial synthesis of both acetone and phenol (Problem 16.65), is synthesized industrially by treating benzene with propene in the presence of phosphoric acid as a catalyst. [Pg.967]

The most widely used industrial synthesis of phenol is based on isopropylbenzene (cumene) as the starting material and is shown m the third entry of Table 24 3 The eco nomically attractive features of this process are its use of cheap reagents (oxygen and sulfuric acid) and the fact that it yields two high volume industrial chemicals phenol and acetone The mechanism of this novel synthesis forms the basis of Problem 24 29 at the end of this chapter... [Pg.1001]

Developments in aliphatic isocyanates include the synthesis of polymeric aliphatic isocyanates and masked or blocked diisocyanates for appflcafions in which volatility or reactivity ate of concern. Polymeric aliphatic isocyanates ate made by copolymerizing methacrylic acid derivatives, such as 2-isocyanatoethyl methacrylate, and styrene [100-42-5] (100). Blocked isocyanates ate prepared via the reaction of the isocyanate with an active hydrogen compound, such as S-caprolactam, phenol [108-95-2] or acetone oxime. [Pg.459]

Fig. 1. Catalytic cycle for synthesis of bisphenol A from phenol and acetone in the presence of a dissociated mineral acid (10). Fig. 1. Catalytic cycle for synthesis of bisphenol A from phenol and acetone in the presence of a dissociated mineral acid (10).
Ciprofibrate (48), a more potent lipid-lowering agent clofibrate, is prepared from Simmons-Smith product by Sandmeyer replacement of the amino group by a hydroxyl via the diazonium salt. Phenol undergoes the Reimer-Thiemann like process common to these agents upon alkaline treatment with acetone and chloroform to complete the synthesis of ci profib-rate (48). [Pg.44]

With OH and SH, the nucleophilic substitution of Cl has been reported. Thus, with NaOH, there is a report of successful nucleophilic substitution in 50% aq. acetone at room temperature to give the phenol complex in 36% yield. The latter is then spontaneously deprotonated to give the cyclohexadienyl complex (Eq. (24)). An identical reaction was carried out using NaSH in MeCN (50% yield) to give the thiophenol complex which was deprotonated [72] Eq. (25). These reactions would be especially valuable because direct synthesis of the phenol or thiophenol complexes from ferrocene is not possible due to the strong interaction between the heteroatom and A1C13 [11, 19]. Recent improvement and use of this reaction were achieved [88],... [Pg.74]

The 1,3,4-oxadiazole 113 is formed from the azo compound 112 by the action of triphenylphosphine <96SL652>. A general synthesis of 1,3.4-oxadiazolines consists in boiling an acylhydrazone with an acid anhydride (e.g., Scheme 18) <95JHC1647>. 2-Alkoxy-2-amino-l,3,4-oxadiazolines are sources of alkoxy(amino)carbenes the spiro compound 114, for instance, decomposes in boiling benzene to nitrogen, acetone and the carbene 115, which was trapped as the phenyl ether 116 in the presence of phenol <96JA4214>. [Pg.219]


See other pages where Synthesis of acetone and phenol is mentioned: [Pg.623]    [Pg.459]    [Pg.623]    [Pg.459]    [Pg.314]    [Pg.129]    [Pg.276]    [Pg.1477]    [Pg.513]    [Pg.339]    [Pg.1142]    [Pg.222]    [Pg.247]    [Pg.78]    [Pg.689]    [Pg.92]    [Pg.73]    [Pg.506]    [Pg.294]    [Pg.174]    [Pg.325]    [Pg.9]    [Pg.384]   
See also in sourсe #XX -- [ Pg.623 ]




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