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Ammonium acetate catalyst

Carboxy-3,5-dichlorophenyl diazo-nium chloride, 31, 97 Catalyst, ammonium acetate, 31, 25, 27 copper chromite, 31, 32 ferric nitrate, hydrated, 31, 53 piperidine, 31, 35 piperidine acetate, 31, 57 Catechol, 33, 74... [Pg.53]

Condensation catalyst. Ammonium acetate is recommended as catalyst for the condensation of ketones with cyanoacetic acid or ethyl cyanoacetate. ... [Pg.753]

The recovered water-soluble catalyst ammonium acetate (NH4OAC) in the filtrate can be recycled for further use. [Pg.57]

The formation of ethyl isopropylidene cyanoacetate is an example of the Knoevenagel reaction (see Discussion before Section IV,123). With higher ketones a mixture of ammonium acetate and acetic acid is an effective catalyst the water formed is removed by azeotropic distillation with benzene. The essential step in the reaction with aqueous potassium cyanide is the addition of the cyanide ion to the p-end of the ap-double bond ... [Pg.490]

Anyway, with catalyst in hand it is time to proceed with the reductive amination [56]. As far as Strike can see, this method will not work well in making MDA. It will not use ammonium acetate in the same way as NaBHaCN. So one is stuck with making MDMA or meth using this method. And without further ado, here s your recipe ... [Pg.121]

For binder preparation, dilute hydrochloric or acetic acids are preferred, because these faciUtate formation of stable silanol condensation products. When more complete condensation or gelation is preferred, a wider range of catalysts, including moderately basic ones, is employed. These materials, which are often called hardeners or accelerators, include aqueous ammonia, ammonium carbonate, triethanolamine, calcium hydroxide, magnesium oxide, dicyclohexylamine, alcohoHc ammonium acetate, and tributyltin oxide (11,12). [Pg.38]

Ammonium acetate and sodium methoxide are effective catalysts for the ammonolysis of soybean oil (49). Polyfunctional amines and amino alcohols such as ethylenediamine, ethanolamine, and diethanolamine react to give useful intermediates. Ethylenediamine can form either a monoamide or a diamide depending on the mole ratio of reactants. With an equimolar ratio of reactants and a temperature of >250° C, a cyclization reaction occurs to give imidazolines with ethylenediamine (48) ... [Pg.85]

Ammonium acetate as catalyst for condensation ot furfural with cyano-acetic add, 40, 47... [Pg.106]

Ethylbenzoic acid was converted to the acid chloride, which was treated with AICI3 and benzene to give 4-ethylbenzophenone in 90% yield overall. Condensation with ethyl cyanoacetate afforded ethyl 4-ethyl-a-cyano-B-phenylcinnamate as an essentially 50/50 mixture of the Z- and E-isomers. The yield of the condensation was highly sensitive to reaction conditions, and was optimized at 75% with portionwise addition of the ammonium acetate catalyst. Bromination and dehydrobromination as described earlier then completed the preparation. The overall yield of ethyl 4-vinyl-a-cyano-p-phenylcinnamate was 20%. [Pg.48]

Trisubstituted imidazoles have been synthesized from 1,2-diketones or a-hydroxyketones with ammonium acetate in very short reaction times with excellent yields in the presence of l,l,3,3-VAr V ,(V -tetramethylguanidinium trifluoroacetate as an ionic liquid <06SC65>. Iodine acted as an efficient catalyst in the synthesis of 1,2,4,5-tetraarylimidazoles 93 using benzoin 91,... [Pg.219]

A typical manganese-salen complex (27)[89] is capable of catalysing the asymmetric epoxidation of (Z)-alkenes (Scheme 18) using sodium hypochlorite (NaOCl) as the principle oxidant. Cyclic alkenes and a, (3-unsaturated esters are also excellent starting materials for example indene may be transformed into the corresponding epoxide (28) with good enantiomeric excess1901. The epoxidation of such alkenes can be improved by the addition of ammonium acetate to the catalyst system 911. [Pg.23]

Another example of a MCR-based strategy for the synthesis of pyridines was reported by Kantevari et al. in 2007. Thus, the three-component condensation of enaminones, 1,3-dicarbonyls, and ammonium acetate in the presence of a catalytic amount of a tangstocobaltate salt as heterogeneous catalyst, either in refluxing solvent or under solvent-free conditions, allowed the regioselective formation of 2,3,6-trisubstituted pyridines and 2,7,7-trisubstituted tetrahydroquinolin-5-ones (Scheme 55) [155]. This methodology combines shorter reaction times and... [Pg.261]

However, all the broad spectrum of products formed via the reaction of salicylic aldehydes with methylene-active nitriles cannot be shown on a one simple scheme. In the presence of ammonium acetate different chromenes 165 and 166 can be isolated, depending on the order of addition of reagents, the amount of catalyst, and temperature (77S871) (Scheme 60). [Pg.214]

To complete the section on the synthesis of 4,4 -bipyridines, we summarize the methods reported for the preparation of some substituted 4,4 -bi-pyridines and 4,4 -bipyridinones. These methods are closely analogous to syntheses already discussed for some of the isomeric bipyridines. Thus the Hantzsch reaction using pyridine-4-aldehyde, ethyl acetoacetate, and ammonia gives 3,5-di(ethoxycarbonyl)-1,4-dihydro-2,6-dimethyl-4,4 -bipyridine, which after oxidation, followed by hydrolysis and decarboxylation, afforded 2,6-dimethyl-4,4 -bipyridine. Several related condensations have been reported. Similarly, pyridine-4-aldehyde and excess acetophenone gave l,5-diphenyl-3-(4-pyridyl)pentane-l,5-dione, which with ammonium acetate afforded 2,6-diphenyl-4,4 -bipyridine. Alternatively, 1-phenyl-3-(4-pyridyl)prop-2-enone, A-phenacylpyridinium bromide, and ammonium acetate gave the same diphenyl-4,4 -bipyridine, and extensions of this synthesis have been discribed. Condensation of pyridine-4-aldehyde with malononitrile in the presence of an alcohol and alkaline catalyst produced compounds such as whereas condensations of... [Pg.330]

An alternative procedure, using sulfuric acid on silica as the catalyst, under solvent-free conditions, gave similar products, and 3-unsubstituted 4(3//)-quinazolinones 893 could also be prepared using ammonium acetate as the amine source <2005TL7051>. [Pg.219]

The film deposition was carried out at room temperature from an aqueous solution of plumbous acetate, ammonium acetate, and ammonium persulphate, using NH4OH to bring the pH to 6. A trace of AgNOs was added as a catalyst for reaction 7.4 [29]. A film of PbOi ca. 50 nm thick was formed in an hour. Once this initial film was deposited, thicker films could be built up, usually at a somewhat higher pH, in the absence of the AgNOs. The initial film formation appears to be a pure CD reaction. However, electrochemical studies of further film buildup showed that an electroless deposition mechanism, involving two partial electrochemical reactions, was responsible for film formation. [Pg.270]

Catalyst, alumina, 34, 79 35, 73 ammonium acetate, 31, 25, 27 boron trifluoride etherate, 38, 26 copper chromite, 31,32 36, 12 copper powder in quinoline for pyrolytic decarboxylation,... [Pg.87]

The water layer (20-25 ml.) contains some acetic acid and acetamide, the acetamide being formed from the ammonium acetate catalyst. [Pg.47]

A number of ketones have been condensed with ethyl cyanoacetate by this procedure. Reactive ketones such as aliphatic methyl ketones and cyclohexanone condense with ethyl cyanoacetate much more rapidly and give better yields of alkyli-dene esters. It is advantageous with such ketones to use a lower ratio of ammonium acetate-acetic acid catalyst.1... [Pg.48]


See other pages where Ammonium acetate catalyst is mentioned: [Pg.495]    [Pg.185]    [Pg.281]    [Pg.370]    [Pg.197]    [Pg.207]    [Pg.37]    [Pg.182]    [Pg.495]    [Pg.161]    [Pg.220]    [Pg.21]    [Pg.259]    [Pg.177]    [Pg.234]    [Pg.315]    [Pg.320]    [Pg.495]    [Pg.132]   
See also in sourсe #XX -- [ Pg.25 , Pg.27 , Pg.31 ]

See also in sourсe #XX -- [ Pg.25 , Pg.27 , Pg.31 ]

See also in sourсe #XX -- [ Pg.25 , Pg.27 , Pg.31 ]

See also in sourсe #XX -- [ Pg.25 , Pg.27 , Pg.31 ]




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