64325-30-0Relevant academic research and scientific papers
Intramolecular aromatic 1,5-hydrogen transfer in free radical reactions III. Reactivity of diaryl ketones, ethers, thioethers, sulfoxydes, and sulfones. An experimental and theoretical study
Karady, Sandor,Cummins, Jordan M.,Dannenberg,Del Rio, Emma,Dormer, Peter G.,Marcune, Benjamin F.,Reamer, Robert A.,Sordo, Tomas L.
, p. 1175 - 1178 (2007/10/03)
(Matrix presented) Experiments show that free radical hydrogen shift is significant in the Pschorr cyclization of diphenyl ethers (X = O) and thioethers (X = S) and does not take place with sufoxides (X = SO) and sulfones (X = SO2). DFT calculations of the product ratios, activation energies, rate constants for H-transfers, and ring-closings at the UB3PW91/6-31G(d,p) level are in excellent agreement with the experimental results reported here and elsewhere in the literature.
Acylation and related reactions under microwaves. 4. Sulfonylation reactions of aromatics
Marquie,Laporterie,Dubac,Roques,Desmurs
, p. 421 - 425 (2007/10/03)
Solvent-free sulfonylation of benzene and its activated or deactivated derivatives were carried out under microwave (MW) irradiation and a catalytic amount of iron(III) chloride, which, under these conditions, is more, active than other metallic salts. With more reactive and/or nonvolatile reagents (anisole, xylenes, mesitylene) expeditious conditions (short reaction time at constant MW power without control of the temperature) were used. With less reactive and/or low-boiling reagents (benzene, toluene, halobenzenes), the rise in temperature and the increase of reaction time were controlled either by sequential MW irradiation or by a temperature order. It was shown that MWs cause preferential interactions with polar species present in the reaction, especially the aryl sulfone and its FeCl3-complexed form. A MW nonthermal effect was not observed when identical temperature gradients were produced by classical heating and MW irradiation, and if reaction temperature was strictly controlled.
Bismuth(III) halides: Remarkable doping agents for triflic acid in the catalytic sulfonylation of arenes
Repichet,Le Roux,Dubac
, p. 9233 - 9234 (2007/10/03)
The catalytic activity of triflic acid has been dramatically increased by the addition of a catalytic amount of bismuth(III) chloride. Thus, the catalytic sulfonylation of arenes using the new system BiCl3-triflic acid has been successfully carried out while both components of this catalytic system are poorly active or inactive alone, which suggests a synergy between BiCl3 and triflic acid. Other bismuth halide-triflic acid systems proved to be active.
Tin for Organic Synthesis, 7. New Regioselective Syntheses of Diaryl Sulfones, Arenesulfonamides, and Arenesulfonic Acid Sodium Salts
Neumann, Wilhelm P.,Wicenec, Christian
, p. 763 - 768 (2007/10/02)
The reaction of (trialkylstannyl)arenes 1 with corresponding reagents containing a chlorosulfonyl group leads, by exclusive ipso substitution, to important diaryl sulfones 2a - i, N-alkylarenesulfonamides 8a - f, and sodium arenesulfonates 13a - c in high yields under mild conditions.The specific leaving ability of the stannyl group allows, moreover, the preparation of arylsulfonyl isomers which are not accessible under the influence of the conventional directing forces of substituents.With N,N-dialkylamidosulfonyl chloride / AlCl3 complexes no destannylation takes place, but the first intramolecular sulfonyltin complex 11 is formed.This result is used to discuss details of the mechanism involved. Key Words: Aromatic substitution, electrophilic / Sulfones, synthesis of / Sulfonamides, synthesis of / Sulfonic acids, sodium salts, synthesis of/ Stannanes, trialkylaryl-, application of
