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Ketones with formaldehyde

Both of these compds yield expls on nitration. It is claimed that these expis have a high detonation velocity, can be pouted at temps below 100°, and are stable when stored at 50° The same investigators proposed the use of nitrates of other cyclic keto-alcohols, such as tetramethylolcyclohexanone, tetramethylolcyclo-pentanone, etc, as expls. All of these alcohols can be prepd by condensing cyclic ketones with formaldehyde in the presence of alkalies or al-... [Pg.408]

N 13 59% oxygen-rich monomer no props are reported except 1R spectrum was prepd by reaction of ethyl methyl ketone with formaldehyde, hydrogenation of the product with Gi chromite catalyst, acetylation to the triacetate, pyrolysis, deacerylation, and nitration of 3,3"bis(hydroxymethyl) -butene-1. The subject compd was synthesized as a binder constituent, which might be polymer-... [Pg.225]

Cyclic Ketone Alcohols or Cycloolkanones, They are prepd by condensation of the corresponding cyclic ketones with formaldehyde in the presence of alkali. They are converted by reduction into cyclic alcohols. Friederich (Ref 1) found that cyclic ketone alcohols (such as tetramethylol-cyclopentanone, tetramethylolcyclohexanone octamethylolcyclohexanedione) and cyclic alcohols (such as tetramethylolcyclopentanol, tertramethylolcyclohexanol, octamethylolcyclo-hexanediol) on nitration yield expl products. [Pg.374]

Beigcr, J. G. and Schoen, K., Reaction of pyrrole ketones with formaldehyde. Formation of N-pyirolc methanols, J. Heterocycl. Chem.. 9, 419, 1972. [Pg.219]

Mannich reaction The reaction of a ketone with formaldehyde in the presence of an amine or ammonia under acidic conditions to give the 3-aminocarbonyl adduct, which is referred to as a Mannich base. After methylation and heating with silver oxide, the a,(3-unsaturated P-carbonyl compound may be formed. [Pg.374]

The base-catalyzed aldol addition reaction of cyclic ketones with formaldehyde is limited by the propensity of the initial hydroxymethyl products to undergo subsequent reactions (e.g. equations 62 and 63). - - Similar problems occur with enolizable aliphatic aldehydes. [Pg.147]

In addition to the side reactions mentioned above, deamination of Mannich bases can occur, especially at elevated temperature, to give a,p-unsaturated derivatives. This route of decomposition of Mannich bases has been exploited as a means of in situ generation of a,p-unsaturated ketones in the Michael reaction and for the direct synthesis of a,3-unsaturated ketones several reviews of the Mannich reaction have discussed aspects of these applications.Recently, a direct one-pot synthesis of a-methylene ketones has been reported involving condensation of ketones with formaldehyde and A -methylaniline tri-fluoroacetate in aptotic solvents. Also, a less direct method has been described in which Mannich bases prepared from 3-keto esters, formaldehyde and dimethylamine are subjected to quatemarization and thermal fragmentation to yield a-methylene ketones.This method is particularly useful for the regios-pecific synthesis of a-methylene ketones because the aminomethylation reaction always takes place at the most activated position flanked by the ketone and ester groups. [Pg.897]

Alkylthioketones are obtained by aldol-type condensations of simple ketones with formaldehyde and a thiol. a-Alkylthio-a -unsaturated carboxylate derivatives may be prepared by Stobbe-type condensations of 5-ethylthioglycollate with aldehydes, or by chlorination-dehydrochlorination of the saturated a-alkyl-thiocarbonyl compounds. ... [Pg.379]

Alcohol synthesis via the reaction of Grignard reagents with carbonyl com pounds (Section 14 6) This is one of the most useful reactions in synthetic organ ic chemistry Grignard reagents react with formaldehyde to yield primary alco hols with aldehydes to give secondary alcohols and with ketones to form terti ary alcohols... [Pg.616]

Other Uses. More than 70 thousand metric tons of acetone is used in smaU volume appHcations some of which are to make functional compounds such as antioxidants, herbicides, higher ketones, condensates with formaldehyde or diphenylamine, and vitamin intermediates. [Pg.99]

Formaldehyde condenses with itself in an aldol-type reaction to yield lower hydroxy aldehydes, hydroxy ketones, and other hydroxy compounds the reaction is autocatalytic and is favored by alkaline conditions. Condensation with various compounds gives methylol (—CH2OH) and methylene (=CH2) derivatives. The former are usually produced under alkaline or neutral conditions, the latter under acidic conditions or in the vapor phase. In the presence of alkahes, aldehydes and ketones containing a-hydrogen atoms undergo aldol reactions with formaldehyde to form mono- and polymethylol derivatives. Acetaldehyde and 4 moles of formaldehyde give pentaerythritol (PE) ... [Pg.491]

MEK is a colorless, stable, flammable Hquid possessing the characteristic acetone-type odor of low molecular weight aUphatic ketones. MEK undergoes typical reactions of carbonyl groups with activated hydrogen atoms on adjacent carbon atoms, and condenses with a variety of reagents. Condensation of MEK with formaldehyde produces methylisopropenyl ketone (3-methyl-3-buten-2-one) ... [Pg.488]

Methyl Isopropyl Ketone. Methyl isopropyl ketone [563-80-4] (3-methyl-2-butanone) is a colorless Hquid with a characteristic odor of lower ketones. It can be produced by hydrating isoprene over an acidic catalyst at 200—300°C (150,151) or by acid-catalyzed condensation of methyl ethyl ketone and formaldehyde to 2-methyl-l-buten-3-one, foUowed by hydrogenation to the product (152). Other patented preparations are known (155,156). Methyl isopropyl ketone is used as an intermediate in the production of pharmaceuticals and fragrances (see Perfumes), and as a solvent (157). It is domestically available from Eastman (Longview, Texas) (47). [Pg.493]

Biacetyl is produced by the dehydrogenation of 2,3-butanediol with a copper catalyst (290,291). Prior to the availabiUty of 2,3-butanediol, biacetyl was prepared by the nitrosation of methyl ethyl ketone and the hydrolysis of the resultant oxime. Other commercial routes include passing vinylacetylene into a solution of mercuric sulfate in sulfuric acid and decomposing the insoluble product with dilute hydrochloric acid (292), by the reaction of acetal with formaldehyde (293), by the acid-cataly2ed condensation of 1-hydroxyacetone with formaldehyde (294), and by fermentation of lactic acid bacterium (295—297). Acetoin [513-86-0] (3-hydroxy-2-butanone) is also coproduced in lactic acid fermentation. [Pg.498]

Reaction with Aldehydes and Ketones. Formaldehyde combines with primary and secondary alkanolamines in the presence of alkali to give methylol derivatives. For the reaction of monoethanolamine with formaldehyde (12), the reaction scheme shown in Figure 1 occurs. [Pg.5]

Reactions with Aldehydes and Ketones. An important use for alkylphenols is ia phenol—formaldehyde resias. These resias are classified as resoles or aovolaks (see Phenolic resins). Resoles are produced whea oae or more moles of formaldehyde react with oae mole of pheaol uader basic catalysis. These resias are thermosets. Novolaks are thermoplastic resias formed whea an excess of phenol reacts with formaldehyde under acidic conditions. The acid protonates formaldehyde to generate the alkylating electrophile (17). [Pg.60]

Quinone Methides. The reaction between aldehydes and alkylphenols can also be base-cataly2ed. Under mild conditions, 2,6-DTBP reacts with formaldehyde in the presence of a base to produce the methylol derivative (22) which reacts further with base to eliminate a molecule of water and form a reactive intermediate, the quinone methide (23). Quinone methides undergo a broad array of transformations by way of addition reactions. These molecules ate conjugated homologues of vinyl ketones, but are more reactive because of the driving force associated with rearomatization after addition. An example of this type of addition is between the quinone methide and methanol to produce the substituted ben2yl methyl ether (24). [Pg.61]

Methyl /-butyl ketone [1634-04-4] (pinacolone) has been prepared in 74% yield by reaction of / f/-amyl alcohol with formaldehyde in the presence of strong acid catalyst (78,79). [Pg.373]

Condensation with Aldehydes and Ketones. Succinic anhydride and succinic esters in the presence of different catalysts react in the gas phase with formaldehyde to give citraconic acid or anhydride and itaconic acid (94—96). Dialkyl acyl succinates are obtained by reaction of dialkyl succinates with C 4 aldehydes over peroxide catalysts (97). [Pg.535]

Several kinds of products can be obtained by reaction of thioglycolic acid and its esters with aldehydes to form mercaptals, RCH(SCH2COOH)2, or with ketones to form thiolketals, RR C(SCH2COOH)2. Reaction with formaldehyde (qv) yields di- -butyhnethylene-bisthioglycolate [1433882-0] (MET ester) ... [Pg.1]

Condensation of vinyl chloride with formaldehyde and HCl (Prins reaction) yields 3,3-dichloro-l-propanol [83682-72-8] and 2,3-dichloro-l-propanol [616-23-9]. The 1,1-addition of chloroform [67-66-3] as well as the addition of other polyhalogen compounds to vinyl chloride are cataly2ed by transition-metal complexes (58). In the presence of iron pentacarbonyl [13463-40-6] both bromoform [75-25-2] CHBr, and iodoform [75-47-8] CHl, add to vinyl chloride (59,60). Other useful products of vinyl chloride addition reactions include 2,2-di luoro-4-chloro-l,3-dioxolane [162970-83-4] (61), 2-chloro-l-propanol [78-89-7] (62), 2-chloropropionaldehyde [683-50-1] (63), 4-nitrophenyl-p,p-dichloroethyl ketone [31689-13-1] (64), and p,p-dichloroethyl phenyl sulfone [3123-10-2] (65). [Pg.415]

Ketones react with formaldehyde and perchloric acid to produce 2-isoxazolines and also with urea in a-methylnaphthalene at 200 °C (75MIP41600, 75ZOB2090, 79MI41612) with N-hydroxyurea they produce 3-hydroxy-2-carbamoylisoxazolidines or, after acid treatment, 2-isoxazolines are formed (Scheme 123) (75TL2337). [Pg.97]

The exceptions are formaldehyde, which is nearly completely hydrated in aqueous solution, and aldehydes and ketones with highly electronegative substituents, such as trichloroacetaldehyde and hexafluoroacetone. The data given in Table 8.1 illustrate that the equilibrium constant for hydration decreases with increasing alkyl substitution. [Pg.450]

When the final methylation of either product is effected with formaldehyde, oxidation of the secondary alcohol group occurs simultaneously in each case, and of the two resulting ketones that from product (XIX) proved to be dZ-hygrine, which must therefore have formula (XVII) given above. Another synthesis of dZ-hygrine has been effected recently by Sorm. ... [Pg.102]

The condensation reaction of a CH-acidic compound—e.g. a ketone 3—with formaldehyde 1 and ammonia 2 is called the Mannich reaction, the reaction products 4 are called Mannich bases. The latter are versatile building blocks in organic synthesis, and of particular importance in natural products synthesis. [Pg.194]


See other pages where Ketones with formaldehyde is mentioned: [Pg.410]    [Pg.916]    [Pg.446]    [Pg.374]    [Pg.197]    [Pg.897]    [Pg.446]    [Pg.410]    [Pg.916]    [Pg.446]    [Pg.374]    [Pg.197]    [Pg.897]    [Pg.446]    [Pg.391]    [Pg.362]    [Pg.7]    [Pg.518]    [Pg.437]    [Pg.48]    [Pg.462]    [Pg.600]    [Pg.569]    [Pg.616]   
See also in sourсe #XX -- [ Pg.214 ]




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Formaldehyde reaction with ketones

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