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Halides oximes

Oximes. Halides are convert (BujSn). In this reaction the nitroso a halide. Previously, the more unde si... [Pg.182]

The relative reactivity of pairs of chloride and bromide complexes is often reported and discussed. Recent studies in this category which refer to such pairs of cobalt(in)-amine-halide complexes include those of aquation of cw-[Co(en)g(cyclohexylamine)X] +, of tra 5-[Co(cyclam)(N02)X]+, and of c/j-[Co(phen)2(N02)X]+, in all cases with X = Cl or Br. Similar reactivity comparisons have been made for cobalt(in)-oxime-halide complexes, including the series /ra 5-[Co(dmgH)2LX], with L = semicarbazide or thiosemi-carbazide, and traw-[Co(dmgH)2(tu)X] (in 20% ethanol). In these latter cases X = Cl, Br, or I. Several of these systems will be mentioned again later, in the section on effects of non-leaving ligands. [Pg.168]

The use of oximes as nucleophiles can be quite perplexing in view of the fact that nitrogen or oxygen may react. Alkylation of hydroxylamines can therefore be a very complex process which is largely dependent on the steric factors associated with the educts. Reproducible and predictable results are obtained in intramolecular reactions between oximes and electrophilic carbon atoms. Amides, halides, nitriles, and ketones have been used as electrophiles, and various heterocycles such as quinazoline N-oxide, benzodiayepines, and isoxazoles have been obtained in excellent yields under appropriate reaction conditions. [Pg.307]

Lithium aluminum hydride (LiAlH4) is the most powerful of the hydride reagents. It reduces acid chlorides, esters, lactones, acids, anhydrides, aldehydes, ketones and epoxides to alcohols amides, nitriles, imines and oximes to amines primary and secondary alkyl halides and toluenesulfonates to... [Pg.61]

Oximes can be alkylated by alkyl halides or sulfates. N-Alkylation is a side reaction, yielding a nitrone. " The relative yield of oxime ether and nitrone depends on the nature of the reagents, including the configuration of the oxime, and on the reaction conditions. For example, anri-benzaldoximes give nitrones, while the syn isomers give oxime ethers. " ... [Pg.495]

Answer This branched primary amine can be made from ketone (21) via the oxime (p T 63). A 1,2 C-C disconnection on (21) is good as it needs the symmetrical allylic halide (22). [Pg.134]

Reactive structures that interfere with the biochemical assay (aldehydes, acyl-halides, sulfonyl-halides, Michael acceptors, epoxides, aziridines, oximes, N-oxides). [Pg.445]

Reaction with Propargyl Halides. The indium-mediated coupling of propargyl bromide with a variety of imines and imine oxides afforded homo-propargylamine derivatives in aqueous media under mild conditions.78 Propargylation of glyoxylic oxime ether in the presence of a catalytic amount of palladium(O) complex and indium(I) iodide in aqueous media was also studied (Eq.11.47).79... [Pg.357]

Clerici and Porta reported that phenyl, acetyl and methyl radicals add to the Ca atom of the iminium ion, PhN+Me=CHMe, formed in situ by the titanium-catalyzed condensation of /V-methylanilinc with acetaldehyde to give PhNMeCHMePh, PhNMeCHMeAc, and PhNMeCHMe2 in 80% overall yield.83 Recently, Miyabe and co-workers studied the addition of various alkyl radicals to imine derivatives. Alkyl radicals generated from alkyl iodide and triethylborane were added to imine derivatives such as oxime ethers, hydrazones, and nitrones in an aqueous medium.84 The reaction also proceeds on solid support.85 A-sulfonylimines are also effective under such reaction conditions.86 Indium is also effective as the mediator (Eq. 11.49).87 A tandem radical addition-cyclization reaction of oxime ether and hydrazone was also developed (Eq. 11.50).88 Li and co-workers reported the synthesis of a-amino acid derivatives and amines via the addition of simple alkyl halides to imines and enamides mediated by zinc in water (Eq. 11.51).89 The zinc-mediated radical reaction of the hydrazone bearing a chiral camphorsultam provided the corresponding alkylated products with good diastereoselectivities that can be converted into enantiomerically pure a-amino acids (Eq. 11.52).90... [Pg.358]

See Sodium acv-nitromethanide, 2-Nitroacetaldehyde oxime Alkylmetal halides... [Pg.184]

Open-chain alkanes, alkyl halide reduction, 29-31 Organosilicon hydrides bond strengths, 5-6 hypervalent silicon species, 9-11 ionic hydrogenation, 5 trivalent silicon species, 7-9 Orthoesters, reduction of, 97-99 Oxime reduction, 102... [Pg.755]

Martynov, I.V., Yu.L. Kruglyak, and S.I. Malekin. "Carbonyl Halide Oxime /S-Chloroalkyl Fluoro-phosphates," Soviet Patent 241433, April 18, 1969 (In Russian). [Pg.102]

Herrmann WA, Brossmer C, Reisinger CP, Riermaier T, Ofele K, Beller M (1997) Coordination chemistry and mechanisms of metal-catalyzed C-C coupling reactions. Part 10. Palladacycles efficient new catalysts for the Heck vinylation of aryl halides. Chem Eur J 3 1357-1364 Iyer S, Jayanthi A (2001) Acetylferrocenyloxime palladacycle-catalyzed Heck reactions. Tetrahedron Lett 42 7877-7878 Iyer S, Ramesh C (2000) Aryl-Pd covalently bonded palladacycles, novel amino and oxime catalysts di- x-chlorobis(benzaldehydeoxime-6-C,AT)dipalla-dium(II), di- x-chlorobis(dimethylbenzylamine-6-C,A)dipalladium(II) for the Heck reaction. Tetrahedron Lett 41 8981-8984 Jeffery T (1984) Palladium-catalysed vinylation of organic halides under solid-liquid phase transfer conditions. J Chem Soc Chem Commun 1287-1289 (b) idem,... [Pg.97]

The oxidation of NH3 to NH2OH forms the basis of a process for the ammoximation of cyclohexanone to the oxime because the NH2OH formed in solution readily reacts with the ketone (non-catalytically) to give the oxime (231). Table XXX (165) illustrates the conversions and selectivites obtained for a few typical ketones and aldehydes. The ammoximation of aldehydes is faster than that of ketones. The oxime selectivity is also higher. The ammoximation of cyclohexanone by this method offers a more eco-friendly alternative route to the cyclohexanone oxime intermediate for the production of Nylon-6. The current route coproduces large quantities of ammonium sulfate and involves the use of hazardous chemicals such as oleum, halides, and oxides of nitrogen. [Pg.114]

The attack by the thiolate anion on the N-oxide oxygen of 62 produces the intermediate sulfenic acid derivative 65, which, in the presence of thiols, further reacts with the thiolate anion, to give the oxime 66, which has been isolated among the reaction products. By contrast, spontaneous loss of the halide anion from 65 affords the ni-troso intermediate 67 that, by losing NO and the thiyl radical directly, or through 68, produces the a-nitrosoolefm 69. By a Michael type reaction with water this last product immediately yields the final oxime 70, which has been isolated among the reaction products. [Pg.150]

This homologation of an oxime ether may have wider application for coupling of alkyl halides to other substrates such as acrylic esters (equation II). [Pg.29]


See other pages where Halides oximes is mentioned: [Pg.127]    [Pg.90]    [Pg.638]    [Pg.219]    [Pg.168]    [Pg.215]    [Pg.150]    [Pg.200]    [Pg.223]    [Pg.943]    [Pg.1656]    [Pg.390]    [Pg.434]    [Pg.951]    [Pg.56]    [Pg.119]    [Pg.215]    [Pg.5]   
See also in sourсe #XX -- [ Pg.766 ]

See also in sourсe #XX -- [ Pg.21 , Pg.22 , Pg.447 , Pg.456 , Pg.623 ]




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