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Olefination primary alcohols

Cu/ZnO = 30/70 catalyst described in Ref. 39. The hydrogenation products were saturated hydrocarbons in the case of aromatics and the olefin, primary alcohols in the case of oxygenates, and methanol in the case of CO. From Ref. 63. [Pg.286]

Tertiary alcohols are more readily dehydrated than secondary alcohols, whilst primary alcohols are dehydrated with comparative difficulty. Thus the reaction proceeds easily with 33 per cent, sulphuric acid (1 acid 2 water, by volume) for amyl alcohol, but 50 per cent, (by volume) is required for aec.-amyl alcohol. Higher concentrations of acid tend to lead to increasing polymerisation of the olefine and are therefore usually avoided. [Pg.239]

Process Technology. In a typical oxo process, primary alcohols are produced from monoolefins in two steps. In the first stage, the olefin, hydrogen, and carbon monoxide [630-08-0] react in the presence of a cobalt or rhodium catalyst to form aldehydes, which are hydrogenated in the second step to the alcohols. [Pg.457]

The hydrides can also be used to form primary alcohols from either terminal or internal olefins. The olefin and hydride form an alkenyl zirconium, Cp2ZrRCl, which is oxidized to the alcohol. Protonic oxidizing agents such as peroxides and peracids form the alcohol direcdy, but dry oxygen may also be used to form the alkoxide which can be hydrolyzed (234). [Pg.439]

The AE reaction has been applied to a large number of diverse allylic alcohols. Illustration of the synthetic utility of substrates with a primary alcohol is presented by substitution pattern on the olefin and will follow the format used in previous reviews by Sharpless but with more current examples. Epoxidation of substrates bearing a chiral secondary alcohol is presented in the context of a kinetic resolution or a match versus mismatch with the chiral ligand. Epoxidation of substrates bearing a tertiary alcohol is not presented, as this class of substrate reacts extremely slowly. [Pg.54]

The thermolysis of xanthates derived from primary alcohols yields one olefin only. With xanthates from secondary alcohols (acyclic or alicyclic) regioisomeric products as well as fi/Z-isomers may be obtained see below. While acyclic substrates may give rise to a mixture of olefins, the formation of products from alicyclic substrates often is determined by the stereochemical requirements the /3-hydrogen and the xanthate moiety must be syn to each other in order to eliminate via a cyclic transition state. [Pg.53]

Because the olefin geometry in compound 9 will most certainly have a bearing on the stereochemical outcome of the hydroboration step, a reliable process for the construction of the trans trisubsti-tuted olefin in 9 must be identified. A priori, the powerful and predictable Wittig reaction28 could be used to construct E u, [3-unsaturated ester 10 from aldehyde 11. Reduction of the ethoxycarbonyl grouping in 10, followed by benzylation of the resulting primary alcohol, would then complete the synthesis of 9. Aldehyde 11 is a known substance that can be prepared from 2-furylacetonitrile (12). [Pg.192]

The above procedure describes the only known preparation of the inner salt of methyl (carboxysulfamoyl)triethylammonium hydroxide and illustrates the use of this reagent to convert a primary alcohol to the corresponding urethane.2 Hydrolysis of the urethane would then provide the primary amine. The method is limited to primary alcohols secondary and tertiary alcohols are dehydrated to olefins under these conditions, often in synthetically useful yields.2... [Pg.43]

Hydroformylation of Higher Molecular Weight Olefins into Primary Alcohols... [Pg.23]

Me-ester sulfonation has to be carried out at relatively high temperatures as the initial reactions and the decomposition of intermediate products is relatively slow compared with sulfonation reaction rates for alkylbenzenes, primary alcohols, ethoxylated alcohols, and a-olefins. The required aging time for conversion of the intermediates to FAME sulfonation acid is long (about 45 min at 85°C). It is not possible to sulfonate Me-esters without an excess of S03. [Pg.665]

The neutralization process consists of an exothermic reaction between a neutralizing agent and either sulfonic acid (e.g., LAB, a-olefins, FAME) or acid sulfate (e.g., primary alcohols, ethoxylated alcohols). Neutralization can be carried out after prolonged storage if the acid stability permits (LAS, FAMES). [Pg.666]

Alkylbenzenes are the commonest organic feedstocks found in the detergent industry, followed by ethoxylated alcohols, primary alcohols, and, Finally, a-olefins. Methylesters have been minimally applied so far. [Pg.670]

The oxo and modified oxo process involve the reaction of mixed a- and internal olefins with hydrogen and carbon monoxide to give predominantly linear primary alcohols, although both processes yield some branched alcohols. [Pg.672]

In 2009, Tu et al. developed a novel iron-catalyzed C(sp )-C(sp ) bond-forming reaction between alcohols and olefins or tertiary alcohols through direct C(sp )-H functionalization. A series of primary alcohols were treated with alkenes or tertiary alcohols as their precursors, using the general catalysis system FeCls (0.15 equiv)/ 1,2-dichloroethane (DCE) (Scheme 36) [46]. [Pg.22]

In 1993, ten challenges faced the catalysis research community. One of these was the anti-Markovnikov addition of water or ammonia to olefins to directly synthesize primary alcohols or amines [323]. Despite some progress, the direct addition of N-H bonds across unsaturated C-C bonds, an apparently simple reaction, stiU remains a challenging fundamental and economic task for the coming century. [Pg.132]

Efficient anti-Markonikov addition of water to terminal olefins producing primary alcohols would be one of the most desirable catalytic processes (Eq. 6.45). As one example of such a reaction, Jensen and Trogler reported the anti-Markonikov hydration of terminal olefins catalyzed by a platinum(II) trimethylphosphine complex producing primary alcohols [83]. The report, however, was claimed to be of doubtful reproducibility [84]. [Pg.199]

The synthesis in Scheme 13.21 starts with a lactone that is available in enantiomer-ically pure form. It was first subjected to an enolate alkylation that was stereocontrolled by the convex shape of the cis ring junction (Step A). A stereospecific Pd-mediated allylic substitution followed by LiAlH4 reduction generated the first key intermediate (Step B). This compound was oxidized with NaI04, converted to the methyl ester, and subjected to a base-catalyzed conjugation. After oxidation of the primary alcohol to an aldehyde, a Wittig-Horner olefination completed the side chain. [Pg.1185]

By 1990, most of the catalytic reactions of TS-1 had been discovered. The wide scope of these reactions is shown in Fig. 6.1.35 Conversions include olefins and diolefins to epoxides,6,7 12 16 19 21 24 34 36 38 13 aromatic compounds to phenols,7,9 19 25 27 36 ketones to oximes,11 20 34 46 primary alcohols to aldehydes and then to acids, secondary alcohols to ketones,34-36 42 47-30 and alkanes to secondary and tertiary alcohols and ketones.6 34 43 31 52... [Pg.232]

Branch and bound techniques, discrete optimization via, 26 1023 Branched aliphatic solvents, 23 104 Branched alkylbenzene (BAB), 77 725 Branched copolymers, 7 610t Branched epoxies, 70 364 Branched olefins, 77 724, 726 Branched polycarbonates, 79 805 Branched polymers, 20 391 Branched primary alcohols, synthetic processes for, 2 2 7t Branching... [Pg.116]

ALDEHYDES FROM PRIMARY ALCOHOLS BY OXIDATION WITH CHROMIUM TRIOXIDE 1-HEPTANAL, 52, 5 ALDEHYDES FROM sym-TRITHIANE n-PENTADECANAL, 51, 39 Aldehydes, acetylenic, 54, 45 Aldehydes, aromatic, 54, 45 Aldehydes, benzyl, 54, 45 Aldehydes, olefinic, 54, 45... [Pg.54]

Oxidation, of primary alcohols to aldehydes, 52, 5 of terminal olefins with chromyl chloride, 51, 6 of 2,4,4-trimethyl-1-pentene with chromyl chloride, 51, 4 with chromium trioxide-pyridine complex, 52, 5... [Pg.62]

Surfactants can be produced from both petrochemical resources and/or renewable, mostly oleochemical, feedstocks. Crude oil and natural gas make up the first class while palm oil (+kernel oil), tallow and coconut oil are the most relevant representatives of the group of renewable resources. Though the worldwide supplies of crude oil and natural gas are limited—estimated in 1996 at 131 X 1091 and 77 X 109 m3, respectively [28]—it is not expected that this will cause concern in the coming decades or even until the next century. In this respect it should be stressed that surfactant products only represent 1.5% of all petrochemical uses. Regarding the petrochemically derived raw materials, the main starting products comprise ethylene, n-paraffins and benzene obtained from crude oil by industrial processes such as distillation, cracking and adsorption/desorption. The primary products are subsequently converted to a series of intermediates like a-olefins, oxo-alcohols, primary alcohols, ethylene oxide and alkyl benzenes, which are then further modified to yield the desired surfactants. [Pg.48]


See other pages where Olefination primary alcohols is mentioned: [Pg.85]    [Pg.150]    [Pg.85]    [Pg.150]    [Pg.886]    [Pg.453]    [Pg.457]    [Pg.458]    [Pg.247]    [Pg.493]    [Pg.244]    [Pg.372]    [Pg.482]    [Pg.509]    [Pg.241]    [Pg.164]    [Pg.73]    [Pg.278]    [Pg.492]    [Pg.15]    [Pg.17]    [Pg.225]    [Pg.227]    [Pg.650]    [Pg.886]    [Pg.34]    [Pg.27]    [Pg.247]    [Pg.361]    [Pg.76]   
See also in sourсe #XX -- [ Pg.335 ]




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Alcohols, primary

Olefin alcohols

Olefine alcohol

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