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Acrylonitrile activation

Duverger-van Bogaert M, Lambotte-Vandepaer M, de Meester C. 1982c. Vinyl chloride and acrylonitrile Activation mechanism and mutagenicity. Toxicol Eur Res 4 35-37. [Pg.101]

Acrylonitrile Activated Charcoal Adacene-12 Adipic Acid... [Pg.19]

Duverger-Van Bogaert, M., Lambotte-Vandepaer, M., de Meester, C., Mercier, M. Poncelet, F. (1982b) Vinyl chloride and acrylonitrile activation mechanism and mutagenicity. Toxicol. Eur. Res., 4, 35-37... [Pg.96]

Acrylic Acid, Isobutyl Ester Acrylic Acid, Methyl Ester Acrylic Aldehyde Acrylic Amide, 50 % Acrylonitrile Activated Charcoal Adacene-12 Adipic Acid... [Pg.127]

Resin polymerized from acrylic acid, methacrylic acid, eaters of these acids, or acrylonitrile. Activation... [Pg.461]

The addition of active methylene compounds (ethyl malonate, ethyl aoeto-acetate, ethyl plienylacetate, nltromethane, acrylonitrile, etc.) to the aP-double bond of a conjugated unsaturated ketone, ester or nitrile In the presence of a basic catalyst (sodium ethoxide, piperidine, diethylamiiie, etc.) is known as the Michael reaction or Michael addition. The reaction may be illustrated by the addition of ethyl malonate to ethyl fumarate in the presence of sodium ethoxide hydrolysis and decarboxylation of the addendum (ethyl propane-1 1 2 3-tetracarboxylate) yields trlcarballylic acid ... [Pg.912]

Unsaturated nitriles are formed by the reaction of ethylene or propylene with Pd(CN)2[252]. The synthesis of unsaturated nitriles by a gas-phase reaction of alkenes. HCN, and oxygen was carried out by use of a Pd catalyst supported on active carbon. Acrylonitrile is formed from ethylene. Methacrylonitrile and crotononitrile are obtained from propylene[253]. Vinyl chloride is obtained in a high yield from ethylene and PdCl2 using highly polar solvents such as DMF. The reaction can be made catalytic by the use of chloranil[254]. [Pg.59]

Addition of HCN to unsaturated compounds is often the easiest and most economical method of making organonitnles. An early synthesis of acrylonitrile involved the addition of HCN to acetylene. The addition of HCN to aldehydes and ketones is readily accompHshed with simple base catalysis, as is the addition of HCN to activated olefins (Michael addition). However, the addition of HCN to unactivated olefins and the regioselective addition to dienes is best accompHshed with a transition-metal catalyst, as illustrated by DuPont s adiponitrile process (6—9). [Pg.217]

Even ia 1960 a catalytic route was considered the answer to the pollution problem and the by-product sulfate, but nearly ten years elapsed before a process was developed that could be used commercially. Some of the eadier attempts iacluded hydrolysis of acrylonitrile on a sulfonic acid ion-exchange resia (69). Manganese dioxide showed some catalytic activity (70), and copper ions present ia two different valence states were described as catalyticaHy active (71), but copper metal by itself was not active. A variety of catalysts, such as Umshibara or I Jllmann copper and nickel, were used for the hydrolysis of aromatic nitriles, but aUphatic nitriles did not react usiag these catalysts (72). Beginning ia 1971 a series of patents were issued to The Dow Chemical Company (73) describiag the use of copper metal catalysis. Full-scale production was achieved the same year. A solution of acrylonitrile ia water was passed over a fixed bed of copper catalyst at 85°C, which produced a solution of acrylamide ia water with very high conversions and selectivities to acrylamide. [Pg.135]

Chain transfer is an important consideration in solution polymerizations. Chain transfer to solvent may reduce the rate of polymerization as well as the molecular weight of the polymer. Other chain-transfer reactions may iatroduce dye sites, branching, chromophoric groups, and stmctural defects which reduce thermal stabiUty. Many of the solvents used for acrylonitrile polymerization are very active in chain transfer. DMAC and DME have chain-transfer constants of 4.95-5.1 x lO " and 2.7-2.8 x lO " respectively, very high when compared to a value of only 0.05 x lO " for acrylonitrile itself DMSO (0.1-0.8 X lO " ) and aqueous zinc chloride (0.006 x lO " ), in contrast, have relatively low transfer constants hence, the relative desirabiUty of these two solvents over the former. DME, however, is used by several acryhc fiber producers as a solvent for solution polymerization. [Pg.277]

A number of activated olefinic compounds react very weU in this scheme including methacrylates, crotonates, acrylonitrile, and vinyl ketones. These reactions are typicaHy mn in an etherial solvent and can be mn without the complications of undesirable side reactions leading to trialkylated tin species. [Pg.547]

Reactions. The chemical properties of cyanoacetates ate quite similar to those of the malonates. The carbonyl activity of the ester function is increased by the cyano group s tendency to withdraw electrons. Therefore, amidation with ammonia [7664-41-7] to cyanoacetamide [107-91-5] (55) or with urea to cyanoacetylurea [448-98-2] (56) proceeds very easily. An interesting reaction of cyanoacetic acid is the Knoevenagel condensation with aldehydes followed by decarboxylation which leads to substituted acrylonitriles (57) such as (29), or with ketones followed by decarboxylation with a shift of the double bond to give P,y-unsaturated nitriles (58) such as (30) when cyclohexanone [108-94-1] is used. [Pg.470]

Poly(vinyl alcohol) undergoes Michaels addition with compounds containing activated double bonds, including acrylonitrile (145—150), acrylamide (151—153), A/-methylolacrylamide (154—156), methyl vinyl ketone (157,158), acrolein (157), and sodium 2-acrylamido-2-methylpropanesulfonate (159). The reactions have been carried out under conditions spanning from homogeneous reactions in solvent to heterogeneous reactions occurring in the swollen powder or fiber. [Pg.481]

Dehydrogenation, Ammoxidation, and Other Heterogeneous Catalysts. Cerium has minor uses in other commercial catalysts (41) where the element s role is probably related to Ce(III)/Ce(IV) chemistry. Styrene is made from ethylbenzene by an alkah-promoted iron oxide-based catalyst. The addition of a few percent of cerium oxide improves this catalyst s activity for styrene formation presumably because of a beneficial interaction between the Fe(II)/Fe(III) and Ce(III)/Ce(IV) redox couples. The ammoxidation of propjiene to produce acrylonitrile is carried out over catalyticaHy active complex molybdates. Cerium, a component of several patented compositions (42), functions as an oxygen and electron transfer through its redox couple. [Pg.371]

Hydrogen cyanide adds to an olefinic double bond most readily when an adjacent activating group is present in the molecule, eg, carbonyl or cyano groups. In these cases, a Michael addition proceeds readily under basic catalysis, as with acrylonitrile (qv) to yield succinonitnle [110-61-2], C4H4N2, iu high yield (13). Formation of acrylonitrile by addition across the acetylenic bond can be accompHshed under catalytic conditions (see Acetylene-DERIVED chemicals). [Pg.376]

The Michael-type addition of maleic hydrazide and other pyridazinones to activated alkenes, such as methyl acrylate, acrylonitrile, methyl vinyl ketone and other a,/3-unsatu-rated carbonyl compounds, results in the formation of mono-lV-substituted products. [Pg.15]

Various alkylating agents are used for the preparation of pyridazinyl alkyl sulfides. Methyl and ethyl iodides, dimethyl and diethyl sulfate, a-halo acids and esters, /3-halo acids and their derivatives, a-halo ketones, benzyl halides and substituted benzyl halides and other alkyl and heteroarylmethyl halides are most commonly used for this purpose. Another method is the addition of pyridazinethiones and pyridazinethiols to unsaturated compounds, such as 2,3(4//)-dihydropyran or 2,3(4//)-dihydrothiopyran, and to compounds with activated double bonds, such as acrylonitrile, acrylates and quinones. [Pg.36]

Kisamori, S., Kuroda, K., Kawano, S., Moehida, 1., Matsumura, Y. and Yoshikawa, M., Oxidative removal of SO2 and recovery of H2SO4 over poly(acrylonitrile)-baacd active carbon fiber. Energy Fuels, 1994, 8(6), 1337 1340. [Pg.115]

The development of new polymer alloys has caused a lot of excitement in recent years but in fact the concept has been around for a long time. Indeed one of the major commercial successes of today, ABS, is in fact an alloy of acrylonitrile, butadiene and styrene. The principle of alloying plastics is similar to that of alloying metals - to achieve in one material the advantages possessed by several others. The recent increased interest and activity in the field of polymer alloys has occurred as a result of several new factors. One is the development of more sophisticated techniques for combining plastics which were previously considered to be incompatible. Another is the keen competition for a share of new market areas such as automobile bumpers, body panels etc. These applications call for combinations of properties not previously available in a single plastic and it has been found that it is less expensive to combine existing plastics than to develop a new monomer on which to base the new plastic. [Pg.11]

Check your predictions by calculating activation energies for Diels-Alder additions. Data for transition states 1-methylcyclopentadiene+acrylonitrile and 1-methyl-cyclopentadiene+acrylonitrile BF3 are available. [Pg.275]

The first step in the Gewald reaction is a Knoevenagel condensation of an activated nitrile with a ketone or aldehyde to produce an acrylonitrile 8, which is then thiolated at the methylene position with elemental sulfur. The sulfurated compound 9 initially decays... [Pg.193]

Attachment of a basic amino group to the side chain leads to a compound with antiparkinsonian activity. Alkylation of the carbanion from phenylacetonitrile with 2-chlorotriethylamine affords the product, 36. Conjugate addition of the anion from this to acrylonitrile gives the glutarodinitrile (37). Partial hydrolysis of this in a mixture of sulfuric and acetic acid leads to phenglutarimide (38). ... [Pg.257]

Fusion of an all cyclic ring onto the piperidine so as to form a perhydroisoquinoline is apparently consistent with analgesic activity. Synthesis of this agent, ciprefadol (68), starts with the Michael addition of the anion from cyclohexanone 56 onto acrylonitrile (57). Saponification of the nitrile to the corresponding acid ( ) followed by Curtius rearrangement leads to isocyanate Acid... [Pg.119]


See other pages where Acrylonitrile activation is mentioned: [Pg.915]    [Pg.135]    [Pg.181]    [Pg.182]    [Pg.182]    [Pg.202]    [Pg.277]    [Pg.167]    [Pg.278]    [Pg.467]    [Pg.100]    [Pg.68]    [Pg.394]    [Pg.437]    [Pg.366]    [Pg.204]    [Pg.419]    [Pg.284]    [Pg.64]    [Pg.95]    [Pg.100]    [Pg.193]    [Pg.104]    [Pg.34]    [Pg.142]    [Pg.87]   
See also in sourсe #XX -- [ Pg.128 ]

See also in sourсe #XX -- [ Pg.128 ]




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