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Halide To amine

Conversion of amines to halides 0-73 Cleavage of tertiary amines (von Braun)... [Pg.1274]

Allylic amines are coupled to halides giving either allylic amines or enamines depending on the reaction condition. Reaction of steroidal dienyl triflate with Boc-diprotected allylamine affords allylamine. Use of AcOK as a base is crucial for the clean coupling[102]. The tert-allylic amine 123 reacts with an aryl halide to give the enamine 125 in DMF and allylic amine 124 in nonpolar solvents[103]. [Pg.145]

In the reaction of aryl and alkenyl halides with 1,3-pentadiene (248), amine and alcohol capture the 7r-allylpalladium intermediate to form 249. In the reactions of o-iodoaniline (250) and o-iodobenzyl alcohol (253) with 1,3-dienes, the amine and benzyl alcohol capture the Tr-allylpalladium intermediates 251 and 254 to give 252 and 255[173-175]. The reaction of o-iodoaniline (250) with 1,4-pen tadiene (256) affords the cyclized product 260 via arylpalladiuni formation, addition to the diene 256 to form 257. palladium migration (elimination of Pd—H and readdition to give 258) to form the Tr-allylpalladium 259, and intramolecular displacement of Tr-allylpalladium with the amine to form 260[176], o-Iodophenol reacts similarly. [Pg.164]

When allene derivatives are treated with aryl halides in the presence of Pd(0), the aryl group is introduced to the central carbon by insertion of one of the allenic bonds to form the 7r-allylpalladium intermediate 271, which is attacked further by amine to give the allylic amine 272. A good ligand for the reaction is dppe[182]. Intramolecular reaction of the 7-aminoallene 273 affords the pyrrolidine derivative 274[183]. [Pg.166]

Lehn s approach is slightly more complex than that illustrated above in that the diol is chloromethylated and then treated with cyanide. Hydrolysis then affords the diacid which may be carried through as shown. It should also be noted that once the bis-acyl halide is in hand, it may be treated directly with an open-chained amine to yield a lipophilic diazacrown, after reduction ... [Pg.351]

Ruonnated carboxylic anhydrides and acyl halides as common acylating reagents to convert amines to amides and to acy late suitable heterocyclic nitiogen atoms have already been described in the first edition [10] Like in the acylation at oxygen, much synthetic activity was concentrated m the past few years on the denvatization of biomolecules by fluoroacylation reactions, that is, tnfluoroacetylation of amino sugars,... [Pg.530]

In 1974, Hegedus and coworkers reported the pa]ladium(II)-promoted addition of secondary amines to a-olefins by analogy to the Wacker oxidation of terminal olefins and the platinum(II) promoted variant described earlier. This transformation provided an early example of (formally) alkene hydroamination and a remarkably direct route to tertiary amines without the usual problems associated with the use of alkyl halide electrophiles. [Pg.136]

Conversion of Acid Halides into Amides Aminolysis Acid chlorides react rapidly with ammonia and amines to give amides. As with the acid chloride plus alcohol method for preparing esters, this reaction of acid chlorides with amines is the most commonly used laboratory method for preparing amides. Both monosubstituted and disubstituted amines can be used, but not trisubstituted amines (R3N). [Pg.803]

The mechanism involves a Pd(0) monocoordinate complex as the active species that undergoes oxidative addition to the aryl halide [141]. Thereafter, coordination of the amine to the palladium centre and deprotonation by the external base results in halide abstraction. After reductive elimination, the coupling product is obtained and the catalytic active species regenerated (Scheme 6.45). [Pg.181]

The alkylation of neutral amines by halides is complicated from a synthetic point of view by the possibility of multiple alkylation that can proceed to the quaternary ammonium salt in the presence of excess alkyl halide. [Pg.229]

Scheme 4.9 gives some examples of the use of boranes in syntheses of alcohols, aldehydes, ketones, amines, and halides. Entry 1 demonstrates both the regioselec-tivity and stereospecificity of hydroboration, resulting in the formation of trans-2-methylcyclohexanol. Entry 2 illustrates the facial selectivity, with the borane adding anti to the endo methyl group. [Pg.347]

The majority of gold(I) carbene complexes are pure organometallic compounds and the are out of the scope of this work. Some halide or triphenylphosphine carbene complexes are known and they will be considered here. Nucleophilic addition of alcohols or amines to gold-coordinated isocyanides is one of the best-established methods to obtain gold carbene derivatives. The reaction of H[Au(CN)2] with propene oxide and estirene oxide yields (cyano)carbene complexes (380) avoiding the intermediate step.2257 A cyclic carbene compound is obtained by reaction of a dinuclear isocyanide with amine (Scheme 32).2258... [Pg.1031]

Methyl transferases are responsible for methylation of a nucleophile, typically using SAM as the carbon donor. They are known to accept a wide range of nucleophiles such as halides (eq. 1 in Figure 13.22) [64], amines (eq. 2 in Figure 13.22) [65], hydroxyls, and enolates. As expected, the reactivity of methyl transfer to halides follows the order of iodide, bromide, and chloride, with chloride being the poorest acceptor. Methylation of amines in nucleotides and proteins plays important roles in biological activities. [Pg.307]

Based on in situ 13C NMR data, surface methoxy groups are reported to form hydrocarbons at temperatures of 523 K and above [273]. The authors have suggested that these hydrocarbons may contribute to the hydrocarbon pool that is established to participate in the catalytic reaction mechanism to form higher hydrocarbons from methanol. Other reactions with amines or halides have also been published [276]. [Pg.217]

The 2,3-substituted indols are formed via a palladium-catalyzed coupling reaction of aryl halide, o-alkenylphenyl isocyanide, and amine (Equation (122)).481 Oxidative addition of an aryl halide, insertion of both the isonitrile and alkene moieties of o-alkenylphenyl isocyanide, and 1,3-hydrogen migration may form a 7r-allylpalladium species, which is then attacked by an amine to afford an indol. [Pg.470]

Aside from alkoxycarbonylations, hydroxycarbonylations in the presence of water to yield allenic carboxylic acids [15] (93, Y = OH) and aminocarbonylations in the presence of amines to give the analogous amides [139] (93, Y = NRR ) have also been carried out, respectively (Scheme 7.13). These products of structure 102 can also be obtained if using the propargylamines 101 with R1 = Ph or R3 Z H as starting materials (Scheme 7.15) [140]. Additionally, hydroxycarbonylations, also termed carboxyla-tions, are successful without palladium catalysis by reaction of propargyl halides and carbon monoxide in the presence of nickel(II) cyanide under phase-transfer conditions [141, 142]. [Pg.372]

FIGURE 4.14 Reactions of activated A-alkoxycarbonylamino acids in the presence of tertiary amine. Acyl halides and mixed and symmetrical anhydrides generate 2-alkoxy-5(4/7)-oxazolone in the presence of tertiary amine. Aminolysis of 2-alkoxy-5(47f)-oxazolone in the presence of E N led to partially epimerized products. OAct = activating group. [Pg.113]

Asymmetric introduction of azide to the a-position of a carbonyl has been achieved by several methods. These include amine to azide conversion by diazo transfer,2 chiral enolate azidation,3 and displacement of optically active trifluoromethanesulfonates,4 p-nitrobenzenesulfonates,5 or halides.6 Alkyl 2-azidopropionates have been prepared in optically active form by diazo transfer,2 p-nitrobenzenesulfonate displacement,5 and the Mitsunobu displacement using zinc azide.7 The method presented here is the simplest of the displacement methods since alcohol activation and displacement steps occur in the same operation. In cases where the a-hydroxy esters are available, this would be the simplest method to introduce azide. [Pg.18]

Zinc, cadmium and mercury are at the end of the transition series and have electron configurations ndw(n + l)s2 with filled d shells. They do not form any compound in which the d shell is other than full (unlike the metals Cu, Ag and Au of the preceding group) these metals therefore do not show the variable valence which is one of the characteristics of the transition metals. In this respect these metals are regarded as non-transition elements. They show, however, some resemblance to the d-metals for instance in their ability to form complexes (with NH3, amines, cyanide, halide ions, etc.). [Pg.471]


See other pages where Halide To amine is mentioned: [Pg.522]    [Pg.1651]    [Pg.213]    [Pg.436]    [Pg.213]    [Pg.586]    [Pg.522]    [Pg.1651]    [Pg.213]    [Pg.436]    [Pg.213]    [Pg.586]    [Pg.28]    [Pg.57]    [Pg.83]    [Pg.289]    [Pg.488]    [Pg.500]    [Pg.510]    [Pg.864]    [Pg.864]    [Pg.255]    [Pg.252]    [Pg.1335]    [Pg.367]    [Pg.1219]    [Pg.155]    [Pg.173]    [Pg.350]    [Pg.518]    [Pg.189]    [Pg.223]    [Pg.154]   
See also in sourсe #XX -- [ Pg.723 ]




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Prior C-X Bond-Forming Coupling Chemistry Related to the Amination of Aryl Halides

To halide

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