A Highly Stereoselective Synthesis of E-(But-1-en-3-yne-1-sulfonyl) hetarenes and Disubstituted 2-Benzothiazolyl Alkynes by Palladium Catalyzed Sonogashira Type Coupling of 2-Chlorovinylsulfones

Chemicals from Alkynes with Palladium Catalysts

“…339 Moreover, activated (E)-2-chlorovinyl sulfones have also been used for the coupling with terminal acetylenes. 340 Vinyl triflates, prepared easily by trapping the corresponding enolate from ketones, can also be used for the palladium-catalyzed Sonogashira coupling with terminal alkynes, giving rise to conjugated enynes. A useful example of this methodology is the cross-coupling of 17-steroidal triflates, such as 284, and terminal alkynes, such as but-3-yn-1-ol, to give 17-alkynylsteroids such as 285 (Scheme 106).…”

“…In addition, ( Z )-1,2-dichloroethylene has also been used for the coupling with amino acid-containing terminal alkynes, in a reaction catalyzed by PdCl 2 (PhCN) 2 (0.05 mol %) and CuI (0.05 mol %) . Moreover, activated ( E )-2-chlorovinyl sulfones have also been used for the coupling with terminal acetylenes …”

Tosyl/pyrrolyl-capped 1,3-enynes via t-BuOK-assisted reaction of TosMIC with acylethynylpyrroles: a new feature of this popular reagent

“…Less described in the literature is the synthesis of sulfonyl-substituted 1,3-enynes. A few known examples (Scheme 1) include the addition of terminal alkynes to acetylenic sulfones in the presence of palladium acetate and tri(2,6-dimethoxyphenyl)phosphane, 17 Sonogashira coupling of halovinyl sulfones with terminal alkynes, 18 the treatment of the trifluoroacylated diethyl 1-(phenylsulfonyl)ethylphosphonate with lithium acetylides or acetylenic Grignard reagents, 19 and three-component reaction of diynes, iodine, and sodium sulfinates giving iodo- and sulfonyl-containing conjugated enynes. 20…”