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With thallium acetate

In room temperature phosphorescence, a treatment of the paper substrate with sodium dodecyl sulfate in conjunction with thallium acetate enhances the results and the technique can be used in routine environmental analysis of organic pollutants [156]. [Pg.273]

Mercuric acetate and thallic acetate have also been used for the oxidative cydiza-tion of vinylallenes (Eq. 13.24) [29]. Exposure of vinylallene 75 to stoichiometric mercuric acetate in acetic acid led to cydopentenone 76 in 75% yield. With thallium acetate as the oxidant, the yield of 76 was 60%. The presumed mechanism of the oxidative cyclization involves a Nazarov cyclization of acetoxymercury intermediate 77. [Pg.828]

Access to the 1,3-benzazepinone 39 has been achieved from aryl iodide 38 with a Pd(0) catalyst, followed by cyclization of the intermediate palladium complex upon reaction with thallium acetate, thus providing a convenient approach to the fused seven-membered ring system (Equation 5) <1998ICA(270)123>. [Pg.249]

Figure 8. Our typical X-ray diffraction patterns of gramicidin—DLPC multilayers with thallium acetate, A, and without salt, B. Eight Bragg orders were recorded. Figure 8. Our typical X-ray diffraction patterns of gramicidin—DLPC multilayers with thallium acetate, A, and without salt, B. Eight Bragg orders were recorded.
A novel Os(t 5-C5H5)- mediated acetato-plus-l,l-diphenyl-2-propyn-l-ol coupling reaction leading to a 2- (Z)-3-acetoxy-1 -hydroxy-1 -phenyl-2-propenyl aryl complex has been also reported (Scheme 41) [60]. Complex 133 reacts with thallium acetate in dichloromethane as solvent to give Os(ti5-C5H5) k -... [Pg.227]

The tetrakis(acetato)metal derivatives M(02CMe)4 (M = Si, Ge, Sn, or Pb) have been prepared by the reaction of metal(rv) halide with thallium acetate (M = Si, Ge, or Sn), or from red lead and acetic acid, all using acetic anhydride as the solvent. All react with potassium acetate to form K2[M(02CMe)6] complexes. The complexes K2[Sn(02CMe)6](MeC0)20 and NMet[Sn(02CMe)5] were also iso-lated. An X-ray study of the latter shows that crystals consist of discrete ions. [Pg.129]

The other way of preparation of fulminates is via the sodium salt. For example, thallium fulminate forms as a fine powder by reaction of sodium fulminate with thallium acetate in methanol [25]. [Pg.65]

Stereoselective cis-dihydroxylation of the more hindered side of cycloalkenes is achieved with silver(I) or copper(II) acetates and iodine in wet acetic acid (Woodward gly-colization J.B. Siddall, 1966 L. Mangoni, 1973 R. Criegee, 1979) or with thallium(III) acetate via organothallium intermediates (E. Glotter, 1976). In these reactions the intermediate dioxolenium cation is supposed to be opened hydrolytically, not by Sn2 reaction. [Pg.128]

Several derivatives of indolo[3,2-fi]carbazole, such as the system 185, have been claimed to arise from the reaction of suitably substituted simple indoles on treatment with thallium triacetate in acetic acid. A compound having the purported structure of 185 was thus isolated when 2,3-dimethylindole was used as the substrate [78UC(B)422]. Many years later, it was demonstrated that this product is in fact a derivative of indolo[2,3-c]carbazole (cf. Section VI) (99T12595). [Pg.37]

Isobutylene oxide is produced in a way similar to propylene oxide and butylene oxide by a chlorohydrination route followed by reaction with Ca(OH)2. Direct catalytic liquid-phase oxidation using stoichiometric amounts of thallium acetate catalyst in aqueous acetic acid solution has been reported. An isobutylene oxide yield of 82% could be obtained. [Pg.251]

Alkenes can also be oxidized with metallic acetates such as lead tetraacetate or thallium(III) acetate " to give bis-acetates of glycols. Oxidizing agents such as benzoquinone, Mn02, or 02, along with palladium acetate, have been used to convert conjugated dienes to l,4-diacetoxy-2-alkenes (1,4 addition). ... [Pg.1051]

Vicinal iodo carboxylates may also be prepared from the reaction of olefins either with iodine and potassium iodate in acetic acid/ or with N-iodosuccinimide and a carboxylic acid in chloroform. " A number of new procedures for effecting the hydroxylation or acyloxylation of olefins in a manner similar to the Prevost or Woodward-Prevost reactions include the following iodo acetoxylation with iodine and potassium chlorate in acetic acid followed by acetolysis with potassium acetate reaction with iV-bromoacetamide and silver acetate in acetic acid reaction with thallium(III) acetate in acetic acid and reaction with iodine tris(trifluoroacetate) in pentane. ... [Pg.88]

Hydroxylamines, V-substituted, 58,108 Hydroxylation with thallium(l) acetate,... [Pg.118]

STEREOSELECTIVE HYDROXYLATION WITH THALLIUM(I) ACETATE AND IODINE trans- AND cis-l,2-CYCLOHEXANEDIOLS... [Pg.220]

Monoalkylthallium(III) compounds are unstable (73, 79), and very few examples of this class have been isolated. A number of alkylthallium diacetates have been obtained either from oxythallation of olefins with thallium-(III) acetate (see below) or from exchange reactions such as that shown in Eq. (11) (74, 75). Only four alkylthallium dihalides have been isolated so far, namely a neopentylthallium dihalide (60) [Eq. (12)] and the isomeric 2-, 3-, and 4-pyridiomethylthallium dichlorides (20) [Eq. (13)]. Monoaryl-and monovinylthallium(III) derivatives are considerably more stable than... [Pg.160]

Formation of mixtures of products in these reactions can be attributed largely to the properties of the acetate group. The reactions of a number of cycloalkenes with thallium(III) salts have been investigated in some detail and the results obtained have served both to elucidate the stereochemistry of oxythallation and to underline the important role assumed by the anion of the metal salt in these oxidations. The most unambiguous evidence as to the stereochemistry of oxythallation comes from studies by Winstein on the oxythallation of norbornene (VII) and norbornadiene (VIII) with thal-lium(III) acetate in chloroform, in which the adducts (IX) and (X) could be precipitated from the reaction mixture by addition of pentane 128) (Scheme 11). Both by chemical means and by analogy with the oxymercuration... [Pg.180]

The same conclusion was drawn from the results obtained from careful studies of the stereochemistry of the glycol products formed on oxidation of cyclohexene with thallium(III) acetate 3, 83). When dry acetic acid was employed as solvent the product was mainly the tranr-diacetate (XI) in moist acetic acid, however, the mixture of glycol mono- (XII) and diacetates (XIII) which was obtained was mainly cis. These results have been interpreted in terms of initial trans oxythallation, ring inversion. [Pg.181]

Oxidation of the steroidal olefin (XXVII) with thallium(III) acetate gives mainly the allylic acetates (XXXI)-(XXXIII) (Scheme 15), again indicating that trans oxythallation is the preferred reaction course (19). Addition of the electrophile takes place from the less-hindered a-side of the molecule to give the thallinium ion (XXVIII), which by loss of a proton from C-4 would give the alkylthallium diacetate (XXIX). Decomposition of this intermediate by a Type 5 process is probably favorable, as it leads to the resonance-stabilized allylic carbonium ion (XXX), from which the observed products can be derived. Evidence in support of the decomposition process shown in Scheme 15 has been obtained from a study of the exchange reaction between frawr-crotylmercuric acetate and thallium(III) acetate in acetic acid (Scheme 16) (142). [Pg.185]

The reactions of TTN with a variety of unsaturated systems have been studied systematically during the last two years, and the results obtained clearly establish the synthetic utility of the reagent as a specific oxidant. Attempts were made in 1966 by Uemura et al. 162) to oxidize a,)8-unsatur-ated carbonyl compounds with thallium(III) acetate, but were unsuccessful. In 1970, however, Ollis and his co-workers 121-123) reported that prolonged treatment of highly activated chalcones (Scheme 20) with thal-... [Pg.189]

The potassium derivatives obtained from the reaction mixture are typically not isolated in pure form, and the crude products are often converted directly to the thallium complexes by metathesis with either thallium nitrate or thallium acetate [Eqs. (1) and (2)]. [Pg.298]

Polarography has also been applied to the determination of potassium in seawater [535]. The sample (1 ml) is heated to 70 °C and treated with 0.1 M sodium tetraphenylborate (1 ml). The precipitated potassium tetraphenylborate is filtered off, washed with 1% acetic acid, and dissolved in 5 ml acetone. This solution is treated with 3 ml 0.1 M thallium nitrate and 1.25 ml 2M sodium hydroxide, and the precipitate of thallium tetraphenylborate is filtered off. The filtrate is made up to 25 ml, and after de-aeration with nitrogen, unconsumed thallium is determined polarographically. There is no interference from 60 mg sodium, 0.2 mg calcium or magnesium, 20 pg barium, or 2.5 pg strontium. Standard eviations at concentrations of 375, 750, and 1125 pg potassium per ml were 26.4, 26.9, and 30.5, respectively. Results agreed with those obtained by flame photometry. [Pg.210]


See other pages where With thallium acetate is mentioned: [Pg.170]    [Pg.210]    [Pg.40]    [Pg.513]    [Pg.201]    [Pg.171]    [Pg.170]    [Pg.210]    [Pg.40]    [Pg.513]    [Pg.201]    [Pg.171]    [Pg.353]    [Pg.210]    [Pg.57]    [Pg.291]    [Pg.923]    [Pg.998]    [Pg.1050]    [Pg.222]    [Pg.162]    [Pg.177]    [Pg.180]    [Pg.182]    [Pg.186]    [Pg.195]    [Pg.199]    [Pg.87]    [Pg.176]   
See also in sourсe #XX -- [ Pg.4 , Pg.72 ]

See also in sourсe #XX -- [ Pg.4 , Pg.72 ]




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Acetate thallium, reaction with

Alkenes oxidation with thallium acetate

Hydroxylation with thallium acetate

Oxidation with thallium acetate

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