N 2-取代的三唑和三嗪衍生物的直接合成一直是N-杂环化学中的挑战。在铜(II)催化下,烯酮N,S-乙缩醛(即烷硫基取代的烯胺酮)与芳基重氮盐有效反应,从而可以选择性选择性地生成功能多样的N2-取代的1,2,3-三唑和2,3-二氢键-1,2,4-三嗪。氧化剂和碱依赖性反应分别产生五元和六元的N-杂环产物。合成方案具有宽泛的底物范围,在温和条件下具有良好的官能团耐受性。机理研究表明,反应是通过烯基偶氮/亚氨基中间体进行的。
These precursors are easily accessible from aryl methyl ketones. Various functional groups like alkyl, aryl, nitrile, amine, aroyl and thiomethyl can be directly installed to the benzene ring. The one-pot approach for the construction of thiomethylated-benzene nucleus was also developed. The structure of the synthesized compound was confirmed by X-ray crystallography.
A convenient base-mediated synthesis of 3-aryol-4-methyl (or benzyl)-2-methylthio furans from α-oxo ketene dithioacetals and propargyl alcohols via domino coupling/annulations
A convenient base-mediated synthesis of 3-aryol-4-methyl (or benzyl)-2-methylthio furans2has been developed through the domino coupling/annulations from α-oxo ketene dithioacetals1and propargyl alcohols.
Tetrasubstituted furans were efficiently synthesized from Fe(OAc)2-catalyzed C–H/C–H cross-dehydrogenative-coupling (CDC) reactions of activated carbonyl methylenes with S,S-functionalized internal olefins, that is, α-oxo ketene dithioacetals and analogues, under oxidative conditions. β-Ketoesters, 1,3-dicarbonyls, β-keto nitrile, and amide derivatives were used as the coupling partners. The resultant
Mediated by a catalytic amount of FeCl3, the C–H alkylation of S,S‐functionalized internal olefins, i.e., α‐oxo ketene dithioacetals and their analogues, was efficiently achieved using simple ethers and toluene derivatives as the coupling partners, di‐tert‐butyl peroxide (DTBP) as the oxidant, and DABCO⋅6 H2O as the additive. The alkylthio functionality is essential for the internal olefinic C–H bond
S-functionalized internal olefins, that is, α-oxo ketene dithioacetals, was efficiently achieved with alcohols as the alkoxylating agents, (diacetoxyiodo)benzene (PhI(OAc)2) as the oxidant, and benzoquinone (BQ) as the co-oxidant. The alkoxylated olefins were thus constructed and applied for the synthesis of alkoxylated N-heterocycles. Polarization of the olefinic carbon-carbon doublebond by the electron-donating