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  • 1
    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.
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  • 2
    ISSN: 1520-6904
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1999 (1999), S. 91-96 
    ISSN: 1434-193X
    Keywords: Alkenes ; Electrophilic additions ; β-Sultones ; sec-Alkyl chlorosulfate ; 2-Chloro-1-alkanesulfonic acid ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: -An exploratory study has been made on the reaction of a number of non-branched alkenes in [D]chloroform as an aprotic solvent, using chlorosulfuric acid as reagent both in the presence and the absence of [D8]1,4-dioxane as complexing agent. Reaction of cyclopentene (1a) with 1.1 mol-equiv. of chlorosulfuric acid in [D]chloroform in the presence of 2.2 mol-equiv. of [D8]1,4-dioxane at 0 °C yielded quantitatively 1,2-cyclopentanesultone (2a). Under similar reaction conditions, the linear alkenes 1b-g afforded the corresponding β-sultones 2b-g. The ClSO3H-dioxane complex acted as a sulfonating reagent with the alkenes to yield the corresponding β-sultones in a syn cycloaddition of SO3 to the Carbon-Carbon double bond. In the absence of [D8]1,4-dioxane the reaction of the linear alkenes 1a-1k in [D]chloroform with chlorosulfuric acid at -40 °C led to the formation of the sec-alkyl chlorosulfates 5a-i, which were formed after initial protonation of the alkene by the strongly acidic ClSO3H. Cyclopentyl chlorosulfate (5a) in [D]chloroform at 0 °C was quantitatively converted into 1,2-cyclopentanesultone (2a). The sec-alkyl chlorosulfates 5b-i at 0 °C gave rise to a mixture of the internal trans- and cis-β-sultones 2b-m. Reaction of 1-octene (1g) with both acetyl sulfate (6a) and trifluoroacetyl sulfate (6b) as reagent in [D]chloroform at -20 °C directly afforded the products 1,2-octanesultone (2g), and the (E) and (Z) isomer of 2-octene-1-sulfonic acid (4g).
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  • 4
    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.
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  • 5
    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.
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  • 6
    Publication Date: 2017-12-01
    Electronic ISSN: 2041-1723
    Topics: Biology , Chemistry and Pharmacology , Natural Sciences in General , Physics
    Published by Springer Nature
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