37510-42-2Relevant academic research and scientific papers
One-Pot Mitsunobu Protocol to Access Ketene S,S-/N,S-Acetals at Room Temperature
Saha, Priya,Ansari, Monish Arbaz,Shukla, Gaurav,Singh, Maya Shankar
supporting information, p. 5884 - 5888 (2021/11/27)
With unique chemical reactivity, α-oxoketene S,S- and N,S-acetals have attracted enormous attention in the past decades, whereas limited reports exist for their synthesis via eco-compatible protocols. Herein, we developed a one-pot protocol for symmetrical and unsymmetrical α-oxoketene S,S-/N,S-acetals through chemoselective alkylation of α-enolic dithioesters using Mitsunobu chemistry at room temperature. The operationally simple and user-friendly mild protocol tolerates a wide range of alcohols and α-enolic dithioesters/β-ketothioamides. Short reaction time, good yields, highly selective C?S functionalization, and E/Z-stereoselectivity are imperative characteristics of this strategy.
Copper-catalyzed trifluoromethylation of internal olefinic C-H bonds: Efficient routes to trifluoromethylated tetrasubstituted olefins and N-heterocycles
Mao, Zhifeng,Huang, Fei,Yu, Haifeng,Chen, Jiping,Yu, Zhengkun,Xu, Zhaoqing
supporting information, p. 3439 - 3445 (2014/04/03)
The functionalization of internal olefins has been a challenging task in organic synthesis. Efficient CuII-catalyzed trifluoromethylation of internal olefins, that is, α-oxoketene dithioacetals, has been achieved by using Cu(OH)2 as a catalyst and TMSCF3 as a trifluoromethylating reagent. The push-pull effect from the polarized olefin substrates facilitates the internal olefinic C-H trifluoromethylation. Cyclic and acyclic dithioalkyl α-oxoketene acetals were used as the substrates and various substituents were tolerated. The internal olefinic C-H bond cleavage was not involved in the rate-determining step, and a mechanism that involves radicals is proposed based on a TEMPO-quenching experiment of the trifluoromethylation reaction. Further derivatization of the resultant CF 3 olefins led to multifunctionalized tetrasubstituted CF3 olefins and trifluoromethylated N-heterocycles.
Unexpected hydrobromic acid-catalyzed C-C bond-forming reactions and facile synthesis of coumarins and benzofurans based on ketene dithioacetals
Yuan, Hongjuan,Wang, Mang,Liu, Yingjie,Wang, Lili,Liu, Jun,Liu, Qun
experimental part, p. 13450 - 13457 (2011/02/27)
Hydrobromic acid was found to be a unique catalyst in C-C bond-forming reactions with ketene dithioacetals. Distinctly different from other acids (including Lewis and Bronsted acids), the remarkable catalytic performance of hydrobromic acid in catalytic a
Synthesis of functionalized allylic sulfoxides and their use in the construction of 2,3,4-trisubstituted furans via a [3 + 2] annulation
Fu, Zhenqian,Wang, Mang,Ma, Yuhui,Liu, Qun,Liu, Jun
, p. 7625 - 7630 (2008/12/22)
(Chemical Equation Presented) A route to 2,3,4-trisubstituted furan derivatives based on a [3 + 2] annulation of functionalized allylic sulfoxides and aldehydes is described. In this strategy, the precursors of allylic sulfoxides 4, allylic sulfides 3, were synthesized via a thiomethylation reaction of an α-EWG ketene-S,S-acetal 1 (EWG: electron-withdrawing group), formaldehyde, and a thiol 2 in high to excellent yields. Allylic sulfoxides 4 were prepared by a highly regioselective oxidation of 3, using m-chloroperoxybenzoic acid as oxidant. Thus, starting from these readily available sulfoxides 4, 2-alkylthio-3,4-disubstituted furans 6 were efficiently constructed via the [3 + 2] annulation reaction of 4 with aldehydes 5 under mild conditions. Further replacement of the 2-alkylthio group of 6 with amines led to the formation of 2-amino-3,4-disubstituted furan derivatives 7.
The Preparation and the Nucleophilic Reaction of 3,3-Di(1-azolyl)-2-alken-1-ones, Precursor of Acetylketene Derivatives
Kashima, Choji,Tajima, Tadakuni,Omote, Yoshimori
, p. 133 - 138 (2007/10/02)
2-Alken-1-ones, 3,3-di-(1-azolyl)-2-alken-1-ones and related compounds were prepared by two methods.These compounds were found to be the useful precursors for acylketene derivatives such as ketene dithioacetals and diaminals by treatment with various nucleophiles.
