通过二芳基二硒化物与末端炔烃的一锅反应来合成标题化合物,从而避免了之前制备芳基硒基炔烃的情况。反应在温和条件下,使用KF / Al 2 O 3和PEG-400作为溶剂,在一定范围的末端炔烃下进行。立体选择性地将二芳基二硒化物加成至炔烃中,以良好的收率仅得到(Z)-1,2-双-芳基-杂戊基烯基烯烃。使用微波辐射将反应时间缩短至几分钟,并且KF / Al 2 O 3 / PEG-400系统可以重复使用一次,而无需事先进行类似活性的处理。
Highly Stereoselective One-Pot Procedure To Prepare Bis- and Tris-chalcogenide Alkenes via Addition of Disulfides and Diselenides to Terminal Alkynes
作者:Angélica Venturini Moro、Cristina W. Nogueira、Nilda B. V. Barbosa、Paulo Henrique Menezes、João Batista Teixeira da Rocha、Gilson Zeni
DOI:10.1021/jo050448o
日期:2005.6.1
conditions, and the addition of dichalcogenides to alkynes occurred stereoselectively to give exclusively the corresponding Z isomers. We observed that the selectivity control was governed by the effective participation of the hydroxyl group from propargyl alcohols. In addition, the bis-chalcogenide alkenes were exclusively obtained with propargyl alcohol having the acidic hydroxyl group proton. Conversely
Novel transition-metal-catalyzed reactions of disulfides and diselenides with acetylenes are described. In the of tetrakis(triphenylphosphine)palladium(0), [Pd(PPh3)4], the (1) of diaryl disulfides and diselenides to terminal acetylenes 1 takes place stereoselectively to give high yields of (Z)-1,2-bis(arylthio)-1-alkenes 2 and (Z)-1,2-bis(arylseleno)-1-alkenes 3, respectively. A mechanistic proposal includes the following: (1) oxidative addition of (ArY)2 [Y = S, Se] to low-valent palladium species, (2) stereoselective cis-thiopalladation or cis-selenopalladation to acetylenes to form a cis-vinylpalladium intermediate, and (3) reductive elimination of the product with retention of the stereochemistry. When the reaction of diaryl disulfides and diselenides with terminal acetylenes is performed under the pressure of carbon monoxide, the carbonylative addition occurs to afford (Z)-1,3-bis(arylthio)-2-alken-1-ones 4 and (Z)-1,3-bis(arylseleno)-2-alken-1-ones 5, respectively. Carbon monoxide is regioselectively incorporated on the side of the terminal carbon of the acetylenes.
A simple and stereoselective synthesis of (Z)-1,2-bis-arylselanyl alkenes from alkynes using KF/Al2O3
作者:Renata G. Lara、Paloma C. Rosa、Liane K. Soares、Márcio S. Silva、Raquel G. Jacob、Gelson Perin
DOI:10.1016/j.tet.2012.08.055
日期:2012.12
The title compounds were synthesized by a one-pot reaction of diaryl diselenides with terminalalkynes avoiding the previous preparation of arylselanyl alkynes. The reactions were performed under mild conditions with a range of terminalalkynes using KF/Al2O3 and PEG-400 as solvent. The addition of diaryl diselenides to alkynes occurred stereoselectively to give exclusively (Z)-1,2-bis-arylselanyl
通过二芳基二硒化物与末端炔烃的一锅反应来合成标题化合物,从而避免了之前制备芳基硒基炔烃的情况。反应在温和条件下,使用KF / Al 2 O 3和PEG-400作为溶剂,在一定范围的末端炔烃下进行。立体选择性地将二芳基二硒化物加成至炔烃中,以良好的收率仅得到(Z)-1,2-双-芳基-杂戊基烯基烯烃。使用微波辐射将反应时间缩短至几分钟,并且KF / Al 2 O 3 / PEG-400系统可以重复使用一次,而无需事先进行类似活性的处理。