Synthesis of γ-Sulfur-Substituted Ketones via Rh(II)/Sc(III) a Cocatalyzed Three-Component Reaction of Diazo Compounds with Thiophenols and Enones

Abstract

A facile method for the synthesis of γ-sulfur-substituted ketones is developed via a Rh(II)/Sc(III) cocatalyzed three-component reaction of diazo compounds with thiophenols and enones. With this method, different γ-sulfur-substituted ketones were obtained in moderate to high yields with good diastereoselectivities.

Copper(II)‐catalyzed Domino Reaction of the Acyclic Ketene‐(S,S)‐Acetals with Diazo Compounds: Convenient Synthesis of Poly‐substituted Thiophenes

“…[23] The intermediate A is then attacked by the acyclic ketene-(S,S)-acetal 1 to deliver a sulfonium ylide B, which produces intermediate C via elimination of [CuL n ]. [13] In the case of α-EWG ketene dithioacetals 1 a-1 c, the product 3 attacked the intermediate A to furnish a sulfonium ylide F, which undergoes elimination of [CuL n ] and CÀ S bond cleavage, leading to the formation of multi-substituted thiophenes 4. [13] In the case of α-EWG ketene dithioacetals 1 a-1 c, the product 3 attacked the intermediate A to furnish a sulfonium ylide F, which undergoes elimination of [CuL n ] and CÀ S bond cleavage, leading to the formation of multi-substituted thiophenes 4.…”

“…[9] In particular, transition-metalcatalyzed reactions of diazo compounds have been highly successful. [11,12] In addition, the situ-generation of sulfur ylides from diazo compounds and sulfide has been well documented for the construction of CÀ S and CÀ C bond [13,14] via the Doyle-Kirmse [15] or Stevens [16] rearrangement reaction. [11,12] In addition, the situ-generation of sulfur ylides from diazo compounds and sulfide has been well documented for the construction of CÀ S and CÀ C bond [13,14] via the Doyle-Kirmse [15] or Stevens [16] rearrangement reaction.…”

“…Screening of copper catalysts revealed that Cu(OTf) 2 was optimal one (entries [2][3][4][5]. Solvent effects have also been observed, and the reaction proceeded well in DCE, while DMF, THF and CH 3 CN are not suitable for this reaction (Table 1, entries [12][13][14]. Solvent effects have also been observed, and the reaction proceeded well in DCE, while DMF, THF and CH 3 CN are not suitable for this reaction (Table 1, entries [12][13][14].…”

“…[10] Pioneered by Doyle and Hu, the applications of electrophilic trapping in situ-generated ylides from metal carbene have become a versatile and useful synthetic strategy for the rapid construction of complex molecules in recent decade. [11,12] In addition, the situ-generation of sulfur ylides from diazo compounds and sulfide has been well documented for the construction of CÀ S and CÀ C bond [13,14] via the Doyle-Kirmse [15] or Stevens [16] rearrangement reaction. In stark contrast, little attention has been paid to cleavage CÀ S bond [17] via sulfur ylide to produce thiophenes.…”

“…At the outset of our studies, we investigated to the multi-substituted thiophene synthesis from the ethyl 2-(bis(ethylthio)methylene)-3-oxobutanoate 1 a with ethyl 2-diazoacetate 2 a via a tandem process. Using CuBr (7 mol%) as a catalyst, desired multi-substituted thiophenes 3 aa and 4 aa were obtained in 48% and 18% yields in DCE under air, respectively ( [12][13][14].…”