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To halide

Both the acid and its salts are powerful reducing agents. They reduce, for example, halogens to halides, and heavy metal cations to the metal. Copper(H) ion is reduced further to give copper(I) hydride, a red-brown precipitate ... [Pg.245]

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]

The presence of a cyano group seems to be important[649]. The reaction has been successfully applied to halides of pyridine, quinoline, isoquinoline, and oxazoles[650]. An interesting application is the synthesis of tetracyanoquino-dimethane (789) by the reaction of / -diiodobenzene with malononitrile[65l]. [Pg.245]

Wastewater occasionally contains hydrogen sulfide and nitrites. These contribute to higher halogen demands. Many of these reactions reduce halogens to halide salts. [Pg.479]

For bromates and iodates, disproportionation to halide and perhalate is not thermodynamically feasible and decomposition occurs either with formation of halide and liberation of O2 (as in the catalysed decomposition of CIOs just considered), or by formation of the oxide ... [Pg.864]

We have explored rare earth oxide-modified amorphous silica-aluminas as "permanent" intermediate strength acids used as supports for bifunctional catalysts. The addition of well dispersed weakly basic rare earth oxides "titrates" the stronger acid sites of amorphous silica-alumina and lowers the acid strength to the level shown by halided aluminas. Physical and chemical probes, as well as model olefin and paraffin isomerization reactions show that acid strength can be adjusted close to that of chlorided and fluorided aluminas. Metal activity is inhibited relative to halided alumina catalysts, which limits the direct metal-catalyzed dehydrocyclization reactions during paraffin reforming but does not interfere with hydroisomerization reactions. [Pg.563]

As an additional probe of metal activity, we monitored benzene hydrogenation activity. As seen in Figure 9, Pt-containing rare earth catalysts have lower hydrogenation activity than chlorided alumina catalysts this result reflects inhibition of metal activity on these supports relative to conventional transitional alumina supports. Whereas the acid strength can be adjusted close to that of chlorided and flourided aluminas, metal activity is somewhat inhibited on these catalysts relative to halided aluminas. This inhibition is not due to dispersion, and perhaps indicates a SMSI interaction between Pt and the dispersed Nd203 phase. [Pg.569]

Another general method for converting alcohols to halides involves reactions with halides of certain nonmetallic elements. Thionyl chloride, phosphorus trichloride, and phosphorus tribromide are the most common examples of this group of reagents. These reagents are suitable for alcohols that are neither acid sensitive nor prone to structural rearrangement. The reaction of alcohols with thionyl chloride initially results in the formation of a chlorosulfite ester. There are two mechanisms by which the chlorosulfite can be converted to a chloride. In aprotic nucleophilic solvents, such as dioxane, solvent participation can lead to overall retention of configuration.7... [Pg.217]

The role of the DEAD is to activate the triphenylphosphine toward nucleophilic attack by the alcohol. In the course of the reaction the N=N double bond is reduced. As is discussed later, this method is applicable for activation of alcohols to substitution by other nucleophiles in addition to halide ions. The activation of alcohols to nucleophilic attack by the triphenylphosphine-DEAD combination is called the Mitsunobu reaction.76... [Pg.221]

Carboxylic acids can be converted to acyl chlorides and bromides by a combination of triphenylphosphine and a halogen source. Triphenylphosphine and carbon tetrachloride convert acids to the corresponding acyl chloride.100 Similarly, carboxylic acids react with the triphenyl phosphine-bromine adduct to give acyl bromides.101 Triphenviphosphine-iV-hromosuccinimide also generates acyl bromide in situ.102 All these reactions involve acyloxyphosphonium ions and are mechanistically analogous to the alcohol-to-halide conversions that are discussed in Section 3.1.2. [Pg.244]

Application of the carbonylation reaction to halides with appropriately placed hydroxy groups leads to lactone formation. In this case the acylpalladium intermediate is trapped intramolecularly. [Pg.752]

Allylic stannanes are an important class of compounds that undergo substitution reactions with alkyl radicals. The chain is propagated by elimination of the trialkyl -stannyl radical.315 The radical source must have some functional group that can be abstracted by trialkylstannyl radicals. In addition to halides, both thiono esters316 and selenides317 are reactive. [Pg.963]

Diazonium salts can also be converted to halides by processes involving aryl free radicals. In basic solutions, aryl diazonium ions are converted to radicals via the diazo oxide.102... [Pg.1031]

The chloride ion is one of the most frequently analysed by IC, e.g. following up combustion of polymers [854,855] similar analyses were reported for the bromide ion [854,855] and nitrite [855]. Analysis of polyester resins for halogens or phosphorous components may be carried out via conversion to halides and phosphates, respectively. [Pg.273]

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]

Reactions of P-halogen-NHPs with Lewis acids leading to halide abstraction, or metathetic replacement of the halide by a nucleofugic, noncoordinating anion form by far the most important routes to access phosphenium ions in general [51, 52] and also 1,3,2-diazaphospholenium cations in particular. As Lewis acid assisted P-X... [Pg.73]

Electron affinity or reduction of halide radical to halide anion (A )... [Pg.242]

There are other synthetic routes to halides similar to compounds (39), which are direct precursors of six-membered cyclic nitronates (35) (Scheme 3.36). [Pg.461]

Patterns for addition of the Schwartz reagent to multiple C—C bonds in terms of regio-and stereochemistry are well-established for most substituents, as is the fundamental chemistry of the newly formed Csp2—Zr and Csp3—Zr bonds. Conversion to halides and... [Pg.110]


See other pages where To halide is mentioned: [Pg.320]    [Pg.119]    [Pg.119]    [Pg.266]    [Pg.126]    [Pg.289]    [Pg.522]    [Pg.862]    [Pg.1651]    [Pg.570]    [Pg.570]    [Pg.221]    [Pg.354]    [Pg.663]    [Pg.703]    [Pg.1335]    [Pg.228]    [Pg.354]    [Pg.24]    [Pg.1219]    [Pg.19]    [Pg.141]    [Pg.173]    [Pg.121]    [Pg.185]    [Pg.187]    [Pg.88]   
See also in sourсe #XX -- [ Pg.3 , Pg.4 ]




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Acid Halides to Amides

Acid Halides to Esters

Acid Halides to Nitriles

Acids to Acid Halides

Acyl halides to ketenes

Acyl halides to ketones

Addition Reactions to Vinyl Halides

Addition of Halides to Cyanamides and Carbodiimides

Addition of Hydrogen Halides to Alkenes

Addition of Hydrogen Halides to Alkynes

Addition of Hydrogen Halides to Conjugated Dienes

Addition of Hydrogen Halides to Nitriles and Isonitriles

Addition of Hydrogen Halides to the Pyrrole Ring

Addition of a Hydrogen Halide to an Alkene

Addition of hydrogen halide to simple unsaturated hydrocarbons

Addition of hydrogen halide to unsaturated alcohols, ethers, carbonyl compounds, and nitriles

Addition of hydrogen halides or halogens to alkenes

Alcohol To halide

Alcohol conversion to alkyl halides with

Alcohols to alkyl halides

Aldehydes, a-alkoxy chiral addition to crotyl halides

Alkyl Halides and Triflates to Alkanes

Alkyl Halides to Alkanecarboxylic Acids

Alkyl Halides to Dialkyl Ethers

Alkyl Halides to Olefines

Alkyl halides to alkanes

Amines to halides

Application to the lattice energy of alkali halides

Carbocation Rearrangements in Hydrogen Halide Addition to Alkenes

Carbocations addition of hydrogen halides to conjugated

Conversion of Alcohols to Alkyl Halides with HX

Conversion of Alcohols to Alkyl Halides with SOCI2 and PBr

Conversion to alkyl halides

Degradation (s. a. Hofmann carboxylic acids to halide

Diazonium ions conversion to aryl halides

Direct Oxidative Addition of Magnesium to Organic Halides

Direct Oxidative Addition of Reactive Zinc to Functionalized Alkyl, Aryl, and Vinyl Halides

Double carbonylation of aryl halides to a-keto acid derivatives

E2 elimination from vinyl halides how to make alkynes

Electrophilic Addition of a Hydrogen Halide to an Alkene

Electrophilic addition of hydrogen halides to alkenes

Halide Allylic, to aldehyde

Halide To aldehyde

Halide To alkene

Halide To alkyl

Halide To ester

Halide To hydride

Halide complexes This page has been reformatted by Knovel to provide easier navigation

Halide-to-ligand charge transfer

Halide-to-metal charge transfer

Halides to Trihalides

Halides to nitriles

Homo-coupling reactions of aryl halides to biaryls catalysed by nickel complexes

Hydrogen halides addition to alkenes

Hydrogen halides addition to alkynes

Hydrogen halides to alkenes

Hydrogen halides to alkenylbenzenes

Hydrogen halides to alkynes

Hydrogen halides to conjugated dienes

Introduction to Alkyl Halides

Ketones, conversion to amides from acyl halides and

Of alkyl halides to alkanes

Of aryl halides to arenes

Organic halides to form esters and amides

Organic halides to form ketones

Organotin Halides with Tin Linked to Anions

Other Methods Used to Convert Alcohols into Alkyl Halides

Other Methods for Converting Alcohols to Alkyl Halides

Other Ways to Prepare Alkyl Halides from Alcohols

Preparation of Active Copper and Reaction with Organic Halides to Yield Organocopper Reagents

Primary conversion to alkyl halides with

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

Reaction with alkyl halides to form

Rearrangements in hydrogen halide addition to alkenes

Reduction to Methylene Halides

Revised Approach to Interpretation of the Data on Transactinoid Halides

Secondary alcohols conversion to alkyl halides with

Secondary conversion to alkyl halides with

Sn2 substitution reactions conversion of alcohols to alkyl halides

Stereoselectivity addition of hydrogen halides to alkenes

To Organo Tellurium Halides

Transfer of Carbamate Group to Alkyl Halides

Use of Halide Ions to Improve Selectivity

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