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Tetraacetate

Lead Tetraacetate. The reduction potential of lead compounds was not included in Table 3.2, but lead tetraacetate [Pb(OAc)4, LTA] is a common reagent for oxidizing organic compounds. The reduction potential for LTA in perchloric acid has been reported to be 1.6 V,502 making it one of the more powerful [Pg.271]

Functionalized alkenes are oxidized with LTA and a variety of interesting transformations are possible.  [Pg.271]

Although lead tetraacetate can attack many polar and nonpolar functions in the steroid molecule, its greatest reactivity is towards vicinal diols. These diols are generally cleaved so rapidly under stoichiometric conditions that other alcohol functions in the molecule need not be protected. Thus lead tetraacetate in acetic acid at room temperature splits the 17a,20-diol group in (9) to yield the 17-ketone (10), the allylic A -3jS-alcohol remaining intact during this oxidation. Since lead tetraacetate is solublein many anhydrous [Pg.242]

If homolytic reaction conditions (heat and nonpolar solvents) can be avoided and if the reaction is conducted in the presence of a weak base, lead tetraacetate is an efficient oxidant for the conversion of primary and secondary alcohols to aldehydes and ketones. The yield of product is in many cases better than that obtained by oxidation with chromium trioxide. The reaction in pyridine is moderately slow the intial red pyridine complex turns to a yellow solution as the reaction progresses, the color change thus serving as an indicator. The method is surprisingly mild and free of side reactions. Thus 17a-ethinyl-17jS-hydroxy steroids are not attacked and 5a-hydroxy-3-ket-ones are not dehydrated. [Pg.242]

SELECTIVE OXIDATIONS OF HYDROXY STEROIDS / 243 EXPERIMENTAL PROCEDURES [Pg.243]

150 ml. of ethanol is agitated with hydrogen in the presence of 3 g. of Raney nickel catalyst [Org. Syntheses, 21, 15 (1945)]. One molar equivalent of hydrogen is absorbed over a period of 16 hours. Removal of the catalyst by filtration, evaporation of the solvent from the filtrate, extraction of the residue with ether, and distillation of the ethereal solution give a 94% yield of lepidine boiling at 126°/40 mm. [Pg.188]


The benzyl group has been widely used for the protection of hydroxyl functions in carbohydrate and nucleotide chemistry (C.M. McCloskey, 1957 C.B. Reese, 1965 B.E. Griffin, 1966). A common benzylation procedure involves heating with neat benzyl chloride and strong bases. A milder procedure is the reaction in DMF solution at room temperatiue with the aid of silver oxide (E. Reinefeld, 1971). Benzyl ethers are not affected by hydroxides and are stable towards oxidants (e.g. periodate, lead tetraacetate), LiAIH, amd weak acids. They are, however, readily cleaved in neutral solution at room temperature by palladium-catalyzed bydrogenolysis (S. Tejima, 1963) or by sodium in liquid ammonia or alcohols (E.J. Rcist, 1964). [Pg.158]

An unactivated methyl group can be functionalized by the cyclopalladation of oximes. The equatorial methyl of geminal methyls in steroids or hexapyr-anosides is selectively aceto.xylated by the reaction of the palladation complex 523 of the 3-oxime with lead tetraacetate[467,468]. [Pg.96]

In Table III-33 results for the methylation of thiazoles in acetic acid are given (lead tetraacetate is used as radical source), but in this case some discrepancies appear, the acidic medium being too weak, and the heterocyclic base not fully protonated. Thiazole has also been methylated by the DMSO-H2O2 method (201), and the results are in agreement with those described previously. [Pg.369]

EGTA ethyleneglycol-bis(P-ami noethyl ether) -N,N -tetraacetic acid 5.4 10.9... [Pg.364]

In the reaction of lead tetraacetate with 1,3- or 1,4-dihydtopetoxides (10) to produce cychc monoperoxides there are two electron transfers to the metal (eq. 14). [Pg.104]

Syimnetiical dialkyl peroxides have been prepared from alkyl hydroperoxides and lead tetraacetate. If tertiary dihydroperoxides are used, then cychc... [Pg.109]

R = cyl), eg, with -nitrobenzoyl chloride. Upon reaction with lead tetraacetate, di(hydroperoxyalkyl) peroxides can also be converted to cycHc diperoxides (4). They are also converted to symmetrical or unsymmetrical cycHc triperoxides (5) in the presence of a second ketone and a catalyst, eg, CuSO -HCl (44,119). [Pg.116]

Similatly, silvet(II) picolinate and lead tetraacetate can be used to produce carbonyl compounds. [Pg.281]

The relationships among the various streptovaricins were shown by the following reactions streptovaricin E (8) converts to streptovaricin C (6) upon treatment with sodium borohydride streptovaricins A (4), G (9), and K (11) yield the same triacetate derivative upon acetylation streptovaricins B (5), C (6), and J (10) yield the same tri- and tetraacetate derivatives upon acetylation streptovaricin G (9) converts to streptovaricin (12) upon treatment with base (4). The open-chain streptovaricin U (13) has also been isolated from the streptovaricin complex (5). [Pg.494]

Treatment of (89) with lead tetraacetate generates the unstable open-ring aldehyde (90) which is quickly converted to a dimethylacetal (91). Following basic hydrolysis of the methyl ester and acetates, the acetal is cleaved with aqueous acid to produce TxB2. A number of other approaches, including one starting from the Corey aldehyde, have been described (58). [Pg.164]

Morpholiaoglucopyranosides have beea syathesized from sucrose by selective lead tetraacetate oxidatioa of the fmctofuranosyl ring to a dialdehyde (6). This product was subjected to reductive amination with sodium borohydride and a primary amine such as benzylamine to produce the /V-henzy1morpho1ino derivative (7) (99). [Pg.35]

Separated polyols are detected by a variety of reagents, including ammoniacal silver nitrate (175), concentrated sulfuric acid, potassium permanganate (163), lead tetraacetate, and potassium teUuratocuprate (176). A mixture of sodium metaperiodate and potassium permanganate can be used to detect as htde as 5—8 ).tg of mannitol or erythritol (177). [Pg.52]

The moderate resistance of DMSO to oxidation permits it to be used as a solvent for oxidations with lead tetraacetate or the 2-nitropropane anion (33,34). Dichromate oxidation and permanganate oxidation have been used for quantitative deterrnination of DMSO (35,36). [Pg.108]

Rosenheim reaction CHCI3 + lead tetraacetate in green fluorescence not given by esters of provitamin D can... [Pg.133]

Fluoride. A fluoride concentration of ca 1 mg/L is helpful in preventing dental caries. Eluoride is deterrnined potentiometrically with an ion-selective electrode. A buffer solution of high total ionic strength is added to the solution to eliminate variations in sample ionic strength and to maintain the sample at pH 5—8, the optimum range for measurement. (Cyclohexylenedinitrilo)tetraacetic acid (CDTA) is usually added to the buffer solution to complex aluminum and thereby prevent its interference. If fluoroborate ion is present, the sample should be distilled from a concentrated sulfuric acid solution to hydrolyze the fluoroborate to free fluoride prior to the electrode measurement (26,27). [Pg.231]

The most suitable oxidizing agent is potassium ferricyanide, but ferric chloride, hydrogen peroxide ia the presence of ferrous salts, ammonium persulfate, lead dioxide, lead tetraacetate or chromate, or silver and cupric salts may be useful. Water mixed, eg, with methanol, dimethylformamide, or glycol ethers, is employed as reaction medium. [Pg.430]

Ethylenediamine tetraacetic acid (EDTA) [60-00-4] (Sequestrene), an anticoagulent at 1 mg of the disodium salt per mL blood, complexes with and removes calcium, Ca ", from the blood. Oxalate, citrate, and fluoride ions form insoluble salts with Ca " and chelate calcium from the blood. Salts containing these anticoagulants include lithium oxalate [553-91-3] 1 mg/mL blood sodium oxalate [62-76-0]2 mg/mL blood ... [Pg.176]

Cleavage of an alkenoic acid can be carried out with permanganate, a permanganate—periodate mixture, periodate or with nitric acid, dichromate, ozone, or, if the unsaturation is first converted to a dihydroxy compound, lead tetraacetate (71,73). Oxidative ozonolysis is a process for the manufacture of azelaic acid [123-99-9] and pelargonic acid (74). [Pg.86]


See other pages where Tetraacetate is mentioned: [Pg.238]    [Pg.48]    [Pg.133]    [Pg.268]    [Pg.102]    [Pg.865]    [Pg.917]    [Pg.920]    [Pg.352]    [Pg.379]    [Pg.559]    [Pg.210]    [Pg.213]    [Pg.517]    [Pg.11]    [Pg.98]    [Pg.27]    [Pg.71]    [Pg.71]    [Pg.71]    [Pg.112]    [Pg.149]    [Pg.214]    [Pg.311]    [Pg.480]    [Pg.429]    [Pg.431]    [Pg.36]    [Pg.40]    [Pg.134]    [Pg.68]    [Pg.394]   
See also in sourсe #XX -- [ Pg.387 ]

See also in sourсe #XX -- [ Pg.96 ]

See also in sourсe #XX -- [ Pg.96 ]

See also in sourсe #XX -- [ Pg.171 ]

See also in sourсe #XX -- [ Pg.387 ]

See also in sourсe #XX -- [ Pg.701 ]




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1,2-diaminocyclohexane tetraacetic acid

1,2-diols lead tetraacetate

1- Aminotriazolopyridine, reaction with lead tetraacetate

1.2- Diaminopropane tetraacetic acid

1.4.7.10- Tetraazacyclododecane-tetraacetate

Acetoxylation Lead tetraacetate

Alcohols with lead tetraacetate

Alcohols, secondary, oxidation with lead tetraacetate

Alcohols, tertiary with lead tetraacetate

Aldopentopyranoses tetraacetates, conformation

Alkenes, reaction with lead tetraacetate

Arabinopyranose 1.2.3.4- tetraacetate

Bisdecarboxylation with Lead Tetraacetate

By lead tetraacetate

Calcium Disodium tetraacetate

Conduritol B tetraacetate

Conduritol tetraacetate

Cyclohexane diamine tetraacetate

Cyclohexanediamine tetraacetate

Cyclohexanediamine tetraacetic acid

Cyclopropanes with lead tetraacetate

Cyclopropanol lead tetraacetate

D tetraacetate

D-Arabinose, diethyl thioacetal, tetraacetate

Decarboxylation lead tetraacetate

Decarboxylation tetraacetate

Dicarboxylic acids reaction with lead tetraacetate

Diethylenetriamine tetraacetate

Dimolybdenum tetraacetate

Diols reaction with lead tetraacetate

Diols, vicinal with lead tetraacetate

Dirhodium tetraacetate

Disodium calcium cyclohexanediamine tetraacetate

Disodium ethylene diamine tetraacetic acid

Disodium ethylene diamine tetraacetic acid EDTA)

Disodium ethylenediamine tetraacetic acid

Disodium tetraacetate

Dulcitol tetraacetate

EDTA (ethylene diamine tetraacetic

Esters Lead tetraacetate

Esters tetraacetate

Ethers tetraacetate

Ethyl ester, tetraacetate

Ethylendiamine tetraacetic acid

Ethylene diamine tetraacetate

Ethylene diamine tetraacetate (edta

Ethylene diamine tetraacetate, determination

Ethylene diamine tetraacetic acid

Ethylene diamine tetraacetic acid EDTA)

Ethylene glycol tetraacetic acid

Ethylenebis tetraacetic acid

Ethylenediamine tetraacetate

Ethylenediamine tetraacetate EDTA)

Ethylenediamine tetraacetic acid

Ethylenediamine tetraacetic acid EDTA)

Ethylenediamine tetraacetic acid, additive

Ethylenediamine tetraacetic acid, and

Ethylenediamine tetraacetic acid, tetrasodium

Ethylenediamine tetraacetic disodium

Ethylenediamine-tetraacetic EDTA

Fragmentation reactions Lead tetraacetate

GLYCERO-D-IDO-NONONONITRILE, 4,8-ANHYDR0-2,3-DIDEOXY-, 5,6,7,9-TETRAACETATE

GLYCERO-D-IDO-NONONONITRILE, 4,8-ANHYDRO-2.3-DIDEOXY 5,6,7,9-TETRAACETATE

Galactose tetraacetate

Glucitol 2,3,4,6-tetraacetate

Glucopyranosyl bromide, 2,3,4,6-tetraacetate

Glucose 3,4,5,6-tetraacetate

Glucose-1,2,3,4-tetraacetate, preparation

Glucosylamine tetraacetate

Glycol cleavage by lead tetraacetate

Glycol-cleavage Oxidation by Lead Tetraacetate

Glycols oxidation with lead tetraacetate

Hexodialdose, alio tetraacetate

Hofmann rearrangement lead tetraacetate

Hydrazones reaction with lead tetraacetate

Hydrazones tetraacetate

Hydroxylation with lead tetraacetate

Ketones by oxidation with lead tetraacetate

Lead tetraacetate

Lead tetraacetate Oxidation of isoquinolines

Lead tetraacetate a-hydroxylation

Lead tetraacetate acetate

Lead tetraacetate action of, on the sugars

Lead tetraacetate agent

Lead tetraacetate aldehydes

Lead tetraacetate alkane oxidation

Lead tetraacetate allylic oxidation

Lead tetraacetate amides, oxidation

Lead tetraacetate aromatic compounds

Lead tetraacetate cleavage

Lead tetraacetate compounds

Lead tetraacetate decarboxylative halogenation

Lead tetraacetate diols, cleavage

Lead tetraacetate for Hofmann rearrangement

Lead tetraacetate fragmentation

Lead tetraacetate glycol cleavage

Lead tetraacetate glycosides

Lead tetraacetate ketone a-acetoxylation

Lead tetraacetate ketones

Lead tetraacetate mechanism

Lead tetraacetate nitriles

Lead tetraacetate organoboranes

Lead tetraacetate oxidation

Lead tetraacetate oxidation of diol

Lead tetraacetate oxidation, comparison

Lead tetraacetate oxidations glycol cleavage mechanisms

Lead tetraacetate oxidations overoxidation

Lead tetraacetate oxidations properties

Lead tetraacetate oxidative

Lead tetraacetate oxidative cleavage of alkenes

Lead tetraacetate oxidative decarboxylation

Lead tetraacetate oxidative decarboxylation of carboxylic acids

Lead tetraacetate oxidative rearrangement

Lead tetraacetate polysaccharides

Lead tetraacetate quinones

Lead tetraacetate reaction

Lead tetraacetate reaction with alcohols

Lead tetraacetate reaction with amines

Lead tetraacetate reaction with ketones

Lead tetraacetate reactions with styrene

Lead tetraacetate reductive decarboxylation

Lead tetraacetate synthesis

Lead tetraacetate vinyl esters

Lead tetraacetate with alkenes

Lead tetraacetate with amides

Lead tetraacetate with amines

Lead tetraacetate with arylthallium

Lead tetraacetate with carboxylate ions

Lead tetraacetate with phenols

Lead tetraacetate with silyl enol ethers

Lead tetraacetate with trimethylsilyl azide

Lead tetraacetate, 204, Table

Lead tetraacetate, and

Lead tetraacetate, assay for

Lead tetraacetate, assay for in functionalization of C-19 methyl

Lead tetraacetate, assay for methanol

Lead tetraacetate, assay for reaction with diphenyl disulfide

Lead tetraacetate, oxidation compound

Lead tetraacetate, oxidation reactions

Lead tetraacetate, oxidative cleavage of dio

Lead tetraacetate-Diphenyl disulfide

Lead tetraacetate-Manganese acetate

Lead tetraacetate-N-Chlorosuccinimide

Lead tetraacetate-Trifluoroacetic acid

Lead tetraacetate-iodine

Mechanisms tetraacetate

N-Sorbitol, l,4-anhydro-6-desoxy-6chloro tetraacetate

Narciclasine tetraacetate

Of lead tetraacetate

Oligosaccharides with lead tetraacetate

Oxidants lead tetraacetate

Oxidation by lead tetraacetate

Oxidation lead tetraacetate, enol acetate

Oxidation lead tetraacetate, of sugars

Oxidation lead tetraacetate, oxidative cyclization

Oxidation reactions Lead tetraacetate-Manganese

Oxidation with lead tetraacetate

Oxidation, basic conditions lead tetraacetate

Oxidation, enzymic with lead tetraacetate

Oxidation—continued with lead tetraacetate

Oxidative with lead tetraacetate

Oximes tetraacetate

Pentaerythritol tetraacetate

Perlin, A. S., Action of Lead Tetraacetate

Perlin, A. S., Action of Lead Tetraacetate on the Sugars

Pyrrole, anhydropolyhydroxyalkyl derivatives tetraacetate

Reaction with lead tetraacetate

Reactions of alcohols with lead tetraacetate

Riboflavin tetraacetate

Ribopyranose tetraacetate

Salt of ethylenediamine-tetraacetic acid

Silicon tetraacetate

Sodium ethylenediamine tetraacetate

Stereoselectivity lead tetraacetate oxidation

Streptovaricin tetraacetate

Sugars action of lead tetraacetate

Tetraacetate 2-amino-2-deoxy

Tetraacetate Oxidation of Cycloalkanols

Tetraacetate, rhodium

Tetraacetic acid lactone, formation

Tetraazacyclododecane-tetraacetic acid

Tetraazacyclododecane-tetraacetic acid DOTA)

The Use of Lead Tetraacetate Hydroxylation at

Thioglucose tetraacetate

Trimethylsilyl azide-lead tetraacetate

Unsaturated carbonyl compounds Lead tetraacetate

With Lead Tetraacetate

Zirconium tetraacetate

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