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Aromatic Sulfonation, 131.Part 130: H. Cerfontain, B. H. Bakker, A. Koeberg-Telder, O. Wilmes, Liebigs Ann. 1997, 49-53. Formation of Sulfonic Acids and Sulfonic Anhydrides in the Sulfur Trioxide Sulfonation of Some Dialkylbenzenes and 1,ω-Diarylalkanes (1997)

Cerfontain, Hans ; Koeberg-Telder, Ankie ; van Lindert, Helen C. A. ; [et al.]

Weinheim : Wiley-Blackwell

Liebigs Annalen 1997 (1997), S. 2227-2233

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ISSN: 0947-3440

Keywords: SO3 sulfonation ; Arenesulfonic acids ; Arenesulfonic anhydrides ; Chemistry ; Organic Chemistry

Source: Wiley InterScience Backfile Collection 1832-2000

Topics: Chemistry and Pharmacology

Notes: An exploratory study has been made on the SO3 sulfonation of a number of alkylarenes in [D2]dichloromethane as an aprotic solvent, mostly in the presence of [D8]1,4-dioxane as a reactivity moderator, in order to obtain information on sulfonic acid and sulfonic anhydride formation. 1,2-Dimethylbenzene (1) with 1.0 mol-equiv. of SO3 yields predominantly the 4-sulfonic acid (1-4-S), whereas with 4.0 mol-equiv. of SO3, 18 mol-% of the corresponding (intermolecular) sulfonic anhydride (1-4-SO2)2O is additionally formed. 1,4-Dimethylbenzene (2) with 0.8 mol-equiv. of SO3 yields predominantly 2-2-S, whereas with 4.0 mol-equiv. of SO3 the sulfonic anhydride (2-2-SO2)2O and its 6-S and 6,6′-S2 derivatives are formed, the eventual main product being (6-S-2-2-SO2)2O. Reaction of 1-ethyl-4-methylbenzene (3) with 2.0 mol-equiv. of SO3-[D8]dioxane at -78 → -40 °C leads to the predominant formation of the 2- and 3-S derivatives in a molar ratio of 26:74, with small amounts of the three corresponding intermolecular anhydrides. Upon performing the sulfonation of 3 at 0 → 22 °C, the relative amounts of the anhydrides are larger, and in addition the 3,5-S2 derivatives of the intermolecular anhydrides are formed. The absence of the isomeric 2,6-S2 derivative is ascribed to the buttressing effect of the 2-sulfo on the 1-ethyl group, hampering the sulfonation at C(6). Reaction of diphenylmethane (4) with 4.2 mol-equiv. of SO3 at -20 → 25 °C yields initially 4-4′-S and subsequently 4-4′,4″-S2. Sulfonation of 1,2-diphenylethane (5) with 4.0 mol-equiv. of SO3 at -78 → 22 °C for 4.5 h leads mainly to the cyclic dimeric disulfonic anhydride [5-4′,4″(-SO2)2O]2, which upon hydrolysis affords 9% of 5-2′,4″- and 91% of 5-4′,4″-S2. However, sulfonation of 5 at 0 → 22 °C for ca. 0.8 h was found to lead to the formation of the intermolecular sulfonic anhydride (4′-S-5-4″-SO2)2O. On sulfonation of 1,2-di-p-tolylethane (6) with 1.0 mol-equiv. of SO3, only ca. 20% of the substrate was sulfonated to give, after hydrolysis, 3% of the 2′- and 12% of the 3′-sulfonate, whereas with 4.0 mol-equiv. of SO3 the initial monosulfonic acids are almost completely converted to yield the 2′,3″,5″-S3, 3′,3″,5″-S3, and 3′,3″,5′,5″-S4.

Additional Material: 9 Tab.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1002/jlac.199719971109

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Aromatic Sulfonation, 130Part 129: H. Cerfontain, A. Koeberg-Telder, R. H. Mitchell, N. Khalifa, M. Tashiro, Recl. Trav. Chim. Pays-Bas 1996, 115, 293-301.. - Relative Intramolecular Reactivity of the Insulated π Double Bond and the 14π Annulene Perimeter toward Sulfur Trioxide in the Sulfonation of IsopyrenesIUPAC name of isopyrene: Azuleno[2,1,8-ija]azulene. (1997)

Cerfontain, Hans ; Bakker, Bert H. ; Koeberg-Telder, Ankie ; [et al.]

Weinheim : Wiley-Blackwell

Liebigs Annalen 1997 (1997), S. 49-53

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ISSN: 0947-3440

Keywords: Sulfur trioxide sulfonation ; [14]Annulene ; [14]Annulenemono- and -disulfonic acids ; β-Sultone and carbyl sulfate (pyrosultone) formation ; Chemistry ; Organic Chemistry

Source: Wiley InterScience Backfile Collection 1832-2000

Topics: Chemistry and Pharmacology

Notes: The sulfonation of isopyrene (1) and its 5-methyl- and 5,10-dimethyl derivative 2 and 3 with SO3 in both dichloromethane and nitromethane as solvent has been studied. Reaction of 1 and 2 leads to sulfodehydrogenation in which SO3 reacts as a monodentate electrophile, the initial products being 1-5-sulfonic acid (1-5-S) and 2-10-S, respectively. In the presence of a sufficiently large amount of SO3 1-5-S is subsequently converted into 1-5,10-S2. With 3, using 2.0 molequiv, of the sulfonating reagent in dichloromethane, the SO3 adds as a bidentate electrophile to the “central C=C bond” with formation of 7,14-dimethyl-1,6:8,13-ethanediylidene-[14]annulene-15,16-sultone (5) and the corresponding pyrosultone 6. Upon subsequent hydrolysis and neutralization with aqueous KOH the eventually obtained product is potasium 16-hydroxy-7,14-dimethyl-1,6:8,13-ethanediylidene-[14]annulene-15-sulfonate (4).

Additional Material: 3 Tab.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1002/jlac.199719970110

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Photoreactions of trans-10b,10c-Dimethyl-10b,10c-dihydropyrenes (1997)

Cerfontain, Hans ; Koeberg-Telder, Ankie ; Bakker, Bert H. ; [et al.]

Weinheim : Wiley-Blackwell

Liebigs Annalen 1997 (1997), S. 873-878

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ISSN: 0947-3440

Keywords: [14]Annulenes ; [2.2]Metacyclophane-1,9-dienes ; Photochemistry ; Photooxidation ; Endoperoxides ; Chemistry ; Organic Chemistry

Source: Wiley InterScience Backfile Collection 1832-2000

Topics: Chemistry and Pharmacology

Notes: The photoisomerization of trans-10b,10c-dimethyl-10b,10c-dihydropyrene (1), its 2,7-di-tert-butyl derivative 5 and a series of potassium sulfonate derivatives of 1, in both [D8]1,4-dioxane and [D2]dichloromethane as solvent, has been studied using λ = 420-570 nm irradiation. Irradiation of a deoxygenated solution of 1 in dioxane leads to the exclusive formation of anti-8,16-dimethyl[2.2]metacyclophane-1,9-diene (2), whereas the photoconversion of 1 in a non-degassed solution leads to the successive formation of 2 and 5,8-epidioxy-anti-8,16-dimethyl[2.2]metacyclophane-1,9-diene (7). Similarly, irradiation of the 2,7-di-tert-butyl derivative 5 in oxygen containing [D8]dioxane as solvent leads to the consecutive formation of the corresponding 5,13-di-tert-butyl derivatives 6 and 8. Irradiation of mixtures of potassium sulfonate derivatives of 1 (1-Sn) in D2O as solvent leads to photoisomerization with formation of the correspondingly substituted sulfonate derivatives of 2. Only with the dipotassium 2,4- and 2,5-disulfonates of 1 eventually small amounts of the corresponding epidioxy-bridged products 7 were formed. The photoisomerization 1-Sn → 2-Sn appeared to be most effective for 1-2-S and 1-2,5-S2 and least effective for 1-2,4,7-S3 and 1-2,4,7,10-S4. In the dark, the epidioxy products 7 and 8 reverted to give initially the corresponding metacyclophanes 2 and 6, and subsequently the respective dihydropyrenes 1 and 5, and the dark reactions of the potassium sulfonate derivatives 2-Sn yielded the correspondingly substituted 1-Sn. A quantitative study showed that the dark reactions steps 7 → 2, 8 → 6, and 2-Sn → 1-Sn (n = 1-4) exhibit first-order kinetics. For the deoxygenation of 5,8-epidioxy-anti-8,16-di-methyl[2.2]metacyclophane-1,9-diene (7) the rate coefficient is ca. 2.7 times that of its 5,13-di-tert-butyl derivative (8), and the rate coefficient for the isomerization 2-Sn → 1-Sn follows the order 2-5-S → 2-5,13-S2 〉 2-1,5,10-S3.

Additional Material: 3 Ill.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1002/jlac.199719970513

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