�ber die Fl�chtigkeit der Kiesels�ure

Kehrmann,; Flürscheim,; Friedheim, Carl; Pinagel, A.

doi:10.1007/bf01304005

Cited by 3 publications

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“…1210 (Pollack, 1893);aminoquinol-HCl (Henrich, 1921) and acetamidoquinol, m.p. 1000 (Kehrmann & Bahatrian, 1898);p-aminothiophenol, m.p. 460 (Hinsberg, 1906) and 4:4'-diaminodiphenyl disulphide, m.p.…”

Section: Methodsmentioning

confidence: 99%

Studies in detoxication. 84. The metabolism of [14C]aniline in the rabbit and other animals

Parke

1960

Biochemical Journal

105

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The fate of aniline in the rabbit was investigated by Smith & Williams (1949), who showed that glucuronides and ethereal sulphates of o-and paminophenol, and possibly 4-aminoresorcinol, were metabolites accounting for 40-45 % of the aniline fed; but the main metabolite, more than 50 % of the dose, was considered to be a labile glucuronide of aniline itself. This labile N-glucuronide was also thought to be the principal metabolite of aniline by

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Section: Methodsmentioning

confidence: 99%

Studies in detoxication. 84. The metabolism of [14C]aniline in the rabbit and other animals

Parke

1960

Biochemical Journal

105

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“…Recently we have disclosed a novel synthetic approach [1] to extended phenalenones as potential precursors of the corresponding odd-alternant hydrocarbons. Here we report the application of this method to the synthesis of the hitherto unknown trinaphthophenalenium cation 4, a cation of a novel C 3h -symmetric odd-alternant hydrocarbon.Treatment [2] of 7H-benzo[hi]chrysen-7-one (1) [3] with 7methoxy-1-naphthyllithium (prepared from 7-methoxy-1naphthyl iodide [4,5] and nBuLi in ether at room temperature) and autooxidation of the resulting adduct in the usual workup afforded 6-(7-methoxy-1-naphthyl)-7H-benzo[hi]chrysen-7one (2) [6] in 75 % yield (Scheme 1). This molecule contains the necessary number of carbons for the construction of the desired trinaphthophenalene skeleton.…”

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“…Treatment [2] of 7H-benzo[hi]chrysen-7-one (1) [3] with 7methoxy-1-naphthyllithium (prepared from 7-methoxy-1naphthyl iodide [4,5] and nBuLi in ether at room temperature) and autooxidation of the resulting adduct in the usual workup afforded 6-(7-methoxy-1-naphthyl)-7H-benzo[hi]chrysen-7one (2) [6] in 75 % yield (Scheme 1). This molecule contains the necessary number of carbons for the construction of the desired trinaphthophenalene skeleton.…”

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Synthesis of the Trinaphthophenalenium Cation

Suenaga

Miyahara

Shimizu

et al. 1998

Angewandte Chemie International Edition

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The unique feature of odd-alternant hydrocarbons (i.e., polycyclic hydrocarbons with alternating double bonds and an odd number of carbon atoms), is the readily interconvertible redox triad (cation ± radical ± anion), which has been the subject of many experimental and theoretical studies. Recently we have disclosed a novel synthetic approach [1] to extended phenalenones as potential precursors of the corresponding odd-alternant hydrocarbons. Here we report the application of this method to the synthesis of the hitherto unknown trinaphthophenalenium cation 4, a cation of a novel C 3h -symmetric odd-alternant hydrocarbon.Treatment [2] of 7H-benzo[hi]chrysen-7-one (1) [3] with 7methoxy-1-naphthyllithium (prepared from 7-methoxy-1naphthyl iodide [4,5] and nBuLi in ether at room temperature) and autooxidation of the resulting adduct in the usual workup afforded 6-(7-methoxy-1-naphthyl)-7H-benzo[hi]chrysen-7one (2) [6] in 75 % yield (Scheme 1). This molecule contains the necessary number of carbons for the construction of the desired trinaphthophenalene skeleton. The methoxy group was deliberately introduced to serve as an auxiliary in the following three key steps of the condensation to the target structure. First, it acts as an electron-donating group to make Scheme 1. Synthesis of 4´CF 3 COO. position 8 reactive enough to react with the central carbonyl group to give 3. Second, it stabilizes the adjacent cationic center as shown in 3 to increase the chance for the ring-closing condensation with the facing benzene ring. Finally, it can leave as methanol to provide the trinaphthophenalenium cation 4.Our system worked as beautifully as we had originally conceived.The reaction proceeded in steps and we could isolate the intermediate 3 as a blue-violet solid after heating 2 in 30 % HBr/HOAc at 958C for 1 h. Although 3 was not fully characterized, the presence of 16 different aromatic protons and three methyl protons in the 1 H NMR spectrum supports the proposed structure. When the reaction temperature was increased to 1108C, the final transannular condensation occurred very smoothly to furnish trinaphthophenalenium trifluoroacetate 4´CF 3 COO as a dark violet solid (71 % from 2) after chromatographic purification (silica gel, CF 3 COOH).The characteristic absorption of 4 in acetonitrile (l max (e) 568 (10 400)) supports its extensively delocalized p system. The 1 H NMR spectrum [7] of 4 consists of four doublets at d 9. 74, 9.42, 9.05, and 9.02 and one triplet at d 8.65 in accord with the expected C 3h symmetry. The FAB mass spectrum (4 in CF 3 COOH/m-nitrobenzyl alcohol matrix) shows a peak for the trinaphthophenalenium cation at m/z 387.1172 (calcd for C 31 H 15 : 387.1174). As a measure of the thermodynamic stability of the trinaphthophenalenium cation, its pK R value was determined by spectrophotometric titration in buffered 50 % aqueous acetonitrile. Although the titration curve was discontinuous [8] between pH 2.65 and 2.96, the preliminary pK R value was estimated to be roughly 4.2. Therefore, the stability of ...

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“…However, prior to the initiation of our study, only three 1,2-disubstituted naphth[ 1,2d]imidazole-4,5-diones had been reported, and their spectral properties had not been studied. In 1898 Kehrmann and Zimmerli (3) reported that the addition of aniline or methylamine to 3-acetamino-l,2naphthoquinone (Ia) followed by air oxidation gave the corresponding 4phenylamino -3acetamino -1,4-naphtho- been studied in an effort to define the scope and Limitations of this reaction. The starting 3-acetamino-l,2-naphthoquinone (1. )…”

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“…The starting 3-acetamino-l,2-naphthoquinone (1. ) was initially prepared by the procedure reported by Kehrmann and Zimmerli (3) and outlined in Chart I1 (Procedure A).…”

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Synthesis of 1,2‐disubstituted naphth [1,2‐d]imidazole‐4,5‐diones

Carroll

Blackwell

1970

Journal of Heterocyclic Chem

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A convenient synthesis of 3‐acylamino‐1,2‐naphthoquinones (I) is presented. The addition of aromatic and aliphatic amines to I followed by exposure to oxygen gives the corresponding 4‐arylamino‐ or 4‐alkylamino‐3‐acylamino‐1,2‐naphthoquinones (II). The addition of 4‐cyclo‐hexylbutylamine to 3‐trichloroacetamino‐1,2‐naphthoquinone took an anomalous course and 1‐(4′‐cyclohexylbutyl)‐3(H)‐naphth[1,2‐d]imidazoline‐2,4,5‐trione (VII) was obtained. Treatment of II with refluxing acetic acid gave 1,2‐disubstituted naphth[1,2‐d]imidazole‐4,5‐diones (III). The reaction was successful with a variety of 4‐substituted amino‐3‐acylamino‐1,2‐naphthoquinones (II) and usually occurred in excellent yield. However, the cyclization of II to III is subject to steric limitation and attempts to cyclize 4‐tert‐butylamino‐3‐acetamino‐1,2‐naphthoquinone to the corresponding imidazole derivative was unsuccessful. The infrared, ultraviolet and nuclear magnetic resonance spectra of I, II, and III are discussed in relation to their structures.

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�ber die Fl�chtigkeit der Kiesels�ure

Cited by 3 publications

References 0 publications

Studies in detoxication. 84. The metabolism of [14C]aniline in the rabbit and other animals

Studies in detoxication. 84. The metabolism of [14C]aniline in the rabbit and other animals

Synthesis of the Trinaphthophenalenium Cation

Synthesis of 1,2‐disubstituted naphth [1,2‐d]imidazole‐4,5‐diones

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