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Industrial processes allyl acetate

The allylation of active methylene compounds with allyl alcohols or their derivatives, called the Tsuji-Trost reaction, is a widely used process in academia as well as in industry. Ranu et al. have reported that the reaction of active methylene compounds with allyl acetate catalyzed by palladium(O) nanoparticles (Scheme 5.22) led to mono-allylation in water, whereas the reaction in THF provided the bis-allylated product. This is a remarkable example of controlling the direction of a reaction by water. [Pg.196]

After these initial results by Tsuji, this elementary step was incorporated into a catalytic process by Hata and co-workers at Toray Industries and by Atkins and co-workers at Union Carbide. These groups reported reactions of allylic phenyl ethers, allylic alcohols, and allylic acetates with carboxylates, alcohols, primary and secondary amines, and methyl acetoacetate catalyzed by Pd(0) complexes and precursors to Pd(0) complexes (Equation 20.3). - After these initial reports, early developments focused on reactions of "soft" carbanions derived from 3-dicarbonyl compounds, cyanoesters, and related compounds containing two electron-withdrawing groups attached to the nucleophilic carbon. Although these reactions occur with allylic halides in the absence of a catalyst, these reactions are greatly accelerated by palladium catalysts. Thus, the palladium catalyst allows these reactions to occur under mild conditions with allylic acfetates, which are more accessible than allylic halides, and with selectivities that are altered by the metal catalyst. [Pg.968]

Anokhina, E. A., Cardona, C. A., Pisarenka, Yu. A., Ponomarev, E. L. (1996). Basic design stages of combined processes by the example of the production of aUyl alcohol by allyl acetate butanolysis. Part 1 the selection of a combined process for the production of allyl alcohol. Chemical Industry in Russia, 9, 537. [Pg.335]

The industrial production of Crixivan (9 H2S04) took advantage of the chirality of (IS,2R)-aminoindanol to set the two central chiral centers of 9 by an efficient diastereoselective alkylation-epoxidation sequence.17 The lithium enolate of 12 reacted with allyl bromide to give 13 in 94% yield and 96 4 diastereoselective ratio. Treatment of a mixture of olefin 13 and V-chlorosuccinimide in isopropyl acetate-aqueous sodium carbonate with an aqueous solution of sodium iodide led to the desired iodohydrin in 92% yield and 97 3 diastereoselectivity. The resulting compound was converted to the epoxide 14 in quantitative yield. Epoxide opening with piperazine 15 in refluxing methanol followed by Boc-removal gave 16 in 94% yield. Finally, treatment of piperazine derivative 16 with 3-picolyl chloride in sulfuric acid afforded Indinavir sulfate in 75% yield from epoxide 14 and 56% yield for the overall process (Scheme 24.1).17-22... [Pg.460]

Discovered more than 70 years ago, hydroformylation is nowadays one of the most important reactions in the chemical industry because aldehydes can be transformed to many other products. In the enantioselective version, rhodium/ diphosphorus ligand complexes are the most important catalytic precursors, although cobalt and platinum complexes have also been widely used. For these systems, the active species are pentacoordinated trigonal-bipyramidal rhodium hydride complexes, [HRh(P-P)(CO)2]. In those complexes, the coordination mode of the bidentate ligand (equatorial-equatorial or equatorial-apical) is an important parameter to explain the outcome of the process. The most common substrates of enantioselective hydroformylation are styrenes followed by vinyl acetate and allyl cyanide. With these substrates, mixtures of the branched (b, chiral) and linear (1, not chiral) aldehydes are usually obtained. In addition, some hydrogenation of the double bond is often observed. Therefore, chemo- and regioselectivity are prerequisites to enan-tioselectivity and all of them must be controlled. An additional eomplieation is that chiral aldehydes are prone to racemise in the presenee of rhodium spe-... [Pg.444]


See other pages where Industrial processes allyl acetate is mentioned: [Pg.217]    [Pg.324]    [Pg.289]    [Pg.320]    [Pg.294]    [Pg.1712]    [Pg.78]    [Pg.36]    [Pg.197]    [Pg.197]    [Pg.270]   


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Acetal allylation

Acetals allylations

Acetic processing

Allyl acetate

Allylic acetals

Allylic acetates

Allylic acetates acetate

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