FeCl<sub>3</sub>/TMSCl:
An Effective Catalytic System for the Conjugate Addition of Sodium <i>p</i>-Toluenesulfinate to α,β-Enones
作者:B. Sreedhar、M. Reddy、P. Reddy
DOI:10.1055/s-2008-1077967
日期:——
A new protocol for the β-sulfonation of α,β-unsaturated carbonyl compounds is described. The method employs FeCl3 as catalyst and TMSCl as additive for conjugate addition of sodium p-toluenesulfinate to enones.
Ethyl Glyoxylate <i>N</i>-Tosylhydrazone as Sulfonyl-Transfer Reagent in Base-Catalyzed Sulfa-Michael Reactions
作者:Maitane Fernández、Uxue Uria、Lucia Orbe、Jose L. Vicario、Efraím Reyes、Luisa Carrillo
DOI:10.1021/jo402518q
日期:2014.1.3
Ethyl glyoxylate N-tosylhydrazone has been identified as an excellent sulfonyl anion surrogate in the DBU-catalyzed conjugate addition reaction with enones and enals for the synthesis of functionalized sulfones. The reaction proceeds under base-catalyzed conditions and provides a direct access to γ-keto- and γ-hydroxy sulfones in a simple and reliable way through a sulfa-Michael reaction that proceeds
Synthesis of<i>cis</i>-Jasmone<i>via</i>the Retroaldol-aldol Condensation of 3-(<i>cis</i>-3-Hexenyl)-2-cyclopentenone in an Autoclave
作者:Takashi Yoshida、Shojiro Saito
DOI:10.1246/bcsj.55.3931
日期:1982.12
cis-Jasmone was efficiently synthesized from 2-cyclopentenone. The treatment of 2-cyclopentenone with sodium p-toluenesulfinate gave 3-(p-tolylsulfonyl)cyclopentanone in a 92.5% yield. The alkylation of the sulfone, after the protection of the ketone, with cis-1-bromo-3-hexene, followed by desulfonylation with 5% hydrochloric acid in tetrahydrofuran, afforded 3-(cis-3-hexenyl)-2-cyclopentenone in a good yield. The retroaldol-aldol condensation of the cyclopentenone in a stainless steel autoclave in presence of 5% sodium hydroxide yielded cis-jasmone in a 80% yield.
Metal-free synthesis of γ-ketosulfones through Brønsted acid-promoted conjugate addition of sulfinamides
作者:Nicolas Gigant、Sami Kayal、Emmanuelle Drège、Delphine Joseph
DOI:10.1039/d3ra08675e
日期:——
A straightforward and general metal-free method has been developed to add sufinamide-derived sulfone units on Michael acceptors under mild conditions. This reaction enables the preparation of a large variety of original γ-ketosulfones, of which only a few synthetic methods have been reported. The mild reaction conditions used tolerate a wide diversity of functional groups and empower the implementation