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Ammonia, allylation

Typical nucleophiles known to react with coordinated alkenes are water, alcohols, carboxylic acids, ammonia, amines, enamines, and active methylene compounds 11.12]. The intramolecular version is particularly useful for syntheses of various heterocyclic compounds[l 3,14]. CO and aromatics also react with alkenes. The oxidation reactions of alkenes can be classified further based on these attacking species. Under certain conditions, especially in the presence of bases, the rr-alkene complex 4 is converted into the 7r-allylic complex 5. Various stoichiometric reactions of alkenes via 7r-allylic complex 5 are treated in Section 4. [Pg.21]

Some nucleophiles other than carbon nucleophiles are allylated. Amines are good nucleophiles. Diethylamine is allylated with allyl alcohol[7]. Allylammes are formed by the reaction of allyl alcohol with ammonia by using dppb as a ligand. Di- and triallylamines are produced commercially from allyl alcohol and ammonia[l74]. [Pg.329]

Treatment of the 9-fiuoro-l,4-dien-3-ol (15) with 3.5 g-atoms of lithium and l-methoxy-2-propanol in ammonia reductively cleaves the allylic 3-hydroxyl group to give t7 corresponding 3-desoxy compound, but the fluorine... [Pg.5]

A variety of conjugated dienones are reduced by lithium-ammonia, presumably via dienyl carbanions analogous to the allyl carbanions encountered in enone reductions. Cross-conjugated l,4-dien-3-ones afford 4-en-3-ones as the major reduction products, indicating that the cyclohexadienyl carbanion (55) protonates largely at C-1. Some protonation at C-5 does occur as shown by examination of the NMR spectrum of the crude reduction product derived from the 17-ethylene ketal of androsta-l,4-diene-3,17-dione. The 17-ethylene ketal of androst-4-ene-3,17-dione is formed in 75%... [Pg.31]

Nickel peroxide is a solid, insoluble oxidant prepared by reaction of nickel (II) salts with hypochlorite or ozone in aqueous alkaline solution. This reagent when used in nonpolar medium is similar to, but more reactive than, activated manganese dioxide in selectively oxidizing allylic or acetylenic alcohols. It also reacts rapidly with amines, phenols, hydrazones and sulfides so that selective oxidation of allylic alcohols in the presence of these functionalities may not be possible. In basic media the oxidizing power of nickel peroxide is increased and saturated primary alcohols can be oxidized directly to carboxylic acids. In the presence of ammonia at —20°, primary allylic alcohols give amides while at elevated temperatures nitriles are formed. At elevated temperatures efficient cleavage of a-glycols, a-ketols... [Pg.248]

Most of the alkylations were carried out by adding a solution of 3,3-ethylenedioxypregna-5,16-dien-20-one in tetrahydrofuran to a solution of lithium in liquid ammonia to the point of color discharge. Treatment with the alkyl halide then furnishes the corresponding 17a-alkyl derivative (10). After hydrolysis of the 3-ketal group, 17a-methyl-, ethyl-, propyl-, butyl-, hexyl-, octyl-, allyl-, and benzylprogesterones are obtained. [Pg.98]

The cyclized analog of meralluride is prepared by a similar synthesis. Thus, condensation of camphoric acid (42) (obtained by oxidation of camphor) with ammonia gives the bicyclic succinimide (44). Reaction with allyl isocyanate followed by ring opening and then reaction with mercuric acetate affords the mercury derivative (45) as the acetate rather than the hydroxide as above. Reaction with sodium chloride converts that acetate to the halide (46). Displacement on mercury with the disodium salt of thioglycollic acid affords the diuretic mercaptomerine (47). ... [Pg.224]

When treated with alcoholic solution of ammonia, it yields thio-sinamine (allyl thiourea), of the formula C3H5. NH. CS. NHj. This body melts at 74°. The formation of this body forms the basis for a method of its determination, which, with other methods, will be found fully described under Oil of Mustard (Vol. I, p. 474). [Pg.294]

A solution of 24.6 g of o-allyl-epoxypropoxybenzene dissolved in 250 ml of absolute ethanol saturated with ammonia was placed in an autoclave and heated on a steam-bath for 2 hours. The alcohol was then removed by distillation and the residue was redissolved in a mixture of methanol and ethylacetate. Hydrogen chloride gas was introduced into the solution. The hydrochloride salt was then precipitated by the addition of ether to yield 11.4 g of product. Five grams of the amine-hydrochloride thus formed were dissolved in 50 ml of methanol and 9 ml of acetone. The resulting solution was cooled to about 0°C. At this temperature 5 g of sodium borohydride were added over a period of 1 hour. Another 2.2 ml of acetone and O.B g of sodium borohydride were added and the solution was kept at room temperature for 1 hour, after which 150 ml of water were added to the solution. The solution was then extracted with three 100-ml portions of ether which were combined, dried over potassium carbonate, and evaporated. The free base was then recrystallized from petrol ether (boiling range 40°-60°C) to yield 2.7 g of material having a melting point of 57°C. [Pg.48]

One gram of 6,7-dihydro-5H-dibenz[c,e] azepine hydrochloride was dissolved in water, made alkaline with concentrated ammonia, and the resultant base extracted twice with benzene. The benzene layers were combined, dried with anhydrous potassium carbonate, and mixed with 0.261 g of allyl bromide at 25°-30°C. The reaction solution became turbid within a few minutes and showed a considerable crystalline deposit after standing 3 A days. The mixture was warmed VA hours on the steam bath in a loosely-stoppered flask, then cooled and filtered. The filtrate was washed twice with water and the benzene layer evaporated at diminished pressure. The liquid residue was dissolved in alcohol, shaken with charcoal and filtered. Addition to the filtrate of 0.3 gram of 85% phosphoric acid in alcohol gave a clear solution which, when seeded and rubbed, yielded 6-allyl-6,7-dihydro-5H-dlbenz[c,e] azepine phosphate, MP about 211°-215°C with decomposition. [Pg.117]

Ammoxidation refers to a reaction in which a methyl group with allyl hydrogens is converted to a nitrile group using ammonia and oxygen in the presence of a mixed oxides-hased catalyst. A successful application of this reaction produces acrylonitrile from propylene ... [Pg.218]

A solution of 1.5 mol equiv of butyllithium in hexane is added to 1.5 mol equiv of a 1 M solution of hexabutylditin in THF at 0 C under nitrogen, and the mixture is stirred for 20 min. The solution is cooled to — 78 °C and a solution of 1.5 mol equiv of diethylaluminum chloride in toluene is added. After stirring for 1 h at — 78 °C, a solution of 0.05 mol equiv of [tetrakis(triphenyl)phosphine]palladium(0) in THF is added followed by a solution of the allyl acetate in THF. The mixture is warmed to r.t., and stirred until the allyl acetate has reacted (TLC). The solution is cooled to 0°C, and an excess of aq ammonia slowly added. After an aqueous workup, the products arc isolated and purified by flash chromatography on silica gel using 1 % triethylamine in the solvent to avoid acid-induced loss of stannane. [Pg.362]

Volatile Inhibitors. Of the volatile components that influence plant growth and development, ethylene has received the most attention. Literature concerned with the variety of effects produced by ethylene, factors which influence its production, and the mechanisms through which responses are expressed has been reviewed by Evenari (57). Other gaseous excretions with inhibitory effects considered by Evenari include hydrogen cyanide, ammonia, essential oils, and mustard oils (probably allyl isothiocyanate and /3-phenethyI isothiocyanate). [Pg.121]

A portion of the product was heated to reflux with methanolic sodium methoxide to convert it into the thermodynamic mixture of trans- (ca. 65%) and cis- (ca. 35%) isomers. Small amounts of the isomers were collected by preparative gas chromatography using an 8 mm. by 1.7 m. column containing 15% Carbowax 20M on Chromosorb W, and each isomer exhibited the expected spectral and analytical properties. The same thermodynamic mixture of isomers was prepared independently by lithium-ammonia reduction5 of 2-allyl-3-methyl-cyclohex-2-enone [2-Cyclohexen-l-one, 3-methyl-2-(2-propcnyl)-],6 followed by equilibration with methanolic sodium methoxide. [Pg.55]

High-boiling products found in this procedure and in similar experiments involving cyclohex-2-enone derivatives5 probably result from bimolecular reduction processes.15 3-Methylcyclohexanone, which arises by protonation rather than alkylation of the enolate (and which made up ca. 12% of the volatile products), is probably the result of reaction of allyl bromide with liquid ammonia to form the acidic species allyl ammonium bromide.5 10... [Pg.56]

BromoaUylamine has been prepared by heating N-(2-bromo-allyl)-phthalimide with hydrazine in methanol 1 by treatment of 2,3-dibromopropylamine hydrochloride with excess alcoholic potassium hydroxide 6 by treatment of 1,2,3-tribromopropane with alcoholic ammonia at 100° and by the present procedure.7... [Pg.8]

ALCOHOL represents a convenient method of converting allyl alcohol to 2-substituted 1-propanols, while a one-pot reaction sequence of alkylation (alkyl lithium) and reduction (lithium—liquid ammonia) provides excellent yields of AROMATIC HYDROCARBONS FROM AROMATIC KETONES AND ALDEHYDES. [Pg.157]

Alternative conditions for reductive decyanations can be used. The allylic ether in compound 26, an intermediate in a total synthesis of (-)-roxaticin, was prone to reduction when treated with lithium in liquid ammonia. Addition of the substrate to an excess of lithium di-ferf-butylbiphenylide in THF at -78°C, and protonation of the alkyllithium intermediate provided the reduced product 27 in 63% yield, as a single diastereomer (Eq. 7). a-Alkoxylithium intermediates generated in this manner are configurationally stable at low temperature, and can serve as versatile synthons for carbon-carbon bond forming processes (see Sect. 4). [Pg.57]

Reactions of 3-chloro-4-enouronate 71 with AgF in acetonitrile (room temp., 12 h) gave the crystalline 3-eno-5-fluorouronate 72 under the Sn2 type of allylic rearrangement the product is unstable and is readily converted into 73 in saturated methanolic ammonia. [Pg.102]

Allyl alcohol + NHs- The coadsorption experiments were made by first putting the catalyst into contact with NH3 at 200°C followed by removal of gaseous NH3 at r.t. and then putting the catalyst with the chemisorbed ammonia into contact with the allyl alcohol at r.t. Using procedures for the coadsorption tests like those used for propylene + NH3, less resolved spectra were obtained. The more remarkable differences in comparison with the analogous spectra for propylene + NH3 (Fig. 3) or acrylic acid + NH3 coadsorption (see below) are that (i) the band in-... [Pg.282]

Co-adsorption experiments show a complex role of the nature and concentration of chemisorbed ammonia species. Ammonia is not only one of the reactants for the synthesis of acrylonitrile, but also reaction with Br()>nsted sites inhibits their reactivity. In particular, IR experiments show that two pathways of reaction are possible from chemisorbed propylene (i) to acetone via isopropoxylate intermediate or (ii) to acrolein via allyl alcoholate intermediate. The first reaction occurs preferentially at lower temperatures and in the presence of hydroxyl groups. When their reactivity is blocked by the faster reaction with ammonia, the second pathway of reaction becomes preferential. The first pathway of reaction is responsible for a degradative pathway, because acetone further transform to an acetate species with carbon chain breakage. Ammonia as NH4 reacts faster with acrylate species (formed by transformation of the acrolein intermediate) to give an acrylamide intermediate. At higher temperatures the amide may be transformed to acrylonitrile, but when Brreform ammonia and free, weakly bonded, acrylic acid. The latter easily decarboxylate forming carbon oxides. [Pg.285]

Rubefacients Produce redness Allyl isothiocyanate 0.5-5% Ammonia water 1 -2.5% Musterole Extra Made by dilution of concentrated solution with water Mustard derivative Pungent odor Avoid inhalation More concentrated solutions are highly caustic Avoid inhalation... [Pg.905]


See other pages where Ammonia, allylation is mentioned: [Pg.650]    [Pg.653]    [Pg.650]    [Pg.653]    [Pg.819]    [Pg.85]    [Pg.2]    [Pg.6]    [Pg.30]    [Pg.259]    [Pg.262]    [Pg.48]    [Pg.95]    [Pg.43]    [Pg.303]    [Pg.53]    [Pg.55]    [Pg.105]    [Pg.500]    [Pg.502]    [Pg.820]    [Pg.286]    [Pg.149]    [Pg.382]   
See also in sourсe #XX -- [ Pg.462 ]




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Ammonia, allylic substitution

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