sp3-sp2 C-C Bond Formation via Brønsted Acid Trifluoromethanesulfonic Acid-Catalyzed Direct Coupling Reaction of Alcohols and Alkenes
作者:Hui-Lan Yue、Wei Wei、Ming-Ming Li、Yong-Rong Yang、Jian-Xin Ji
DOI:10.1002/adsc.201100262
日期:2011.11
A novel and efficient trifluoromethanesulfonic acid-catalyzed sp3-sp2 CC bond formation reaction through the direct coupling of alcohols with alkenes has been realized under mild conditions. The present protocol provides an attractive approach to a diverse range of polysubstituted olefins in good to excellent yields with high stereo- and regioselectivities.
Treatment of (E)- and (Z)-β-styryltrimethylsilanes with benzaldehyde diethyl acetal in the presence of Lewis acid affords selectively 1,3,5-tri-phenyl-(E,E)- and (E,Z)-1,4-pentadienes, respectively.
Calcium-Catalyzed Direct Coupling of Alcohols with Organosilanes
作者:Vera J. Meyer、Meike Niggemann
DOI:10.1002/ejoc.201100231
日期:2011.7
A calcium-catalyzeddirect substitution of π-activatedalcohols with different organosilanes under very mild reaction conditions is presented. The high reactivity of the calcium catalyst allows efficient conversion of secondary and tertiary allylic, secondary benzylic, and tertiary propargylic alcohols with allyltrimethylsilane at room temperature. Furthermore, the first direct substitution of an alcohol
Deaminative Arylation and Alkenyaltion of Aliphatic Tertiary Amines with Aryl and Alkenylboronic Acids via Nitrogen Ylides
作者:Jianke Su、Chengbo Li、Xinyuan Hu、Yu Guo、Qiuling Song
DOI:10.1002/anie.202212740
日期:2022.12.23
arylation and alkenylation of tertiary amines with aryl and alkenylboronic acids is enabled by difluorocarbene under transition-metal-free conditions. This protocol represents a novel reaction mode which succeeded in the construction of Csp3−Csp2 bonds via an in situ formed nitrogen ylide from tertiary amines (propargylamines, allylamines and 1H-indol-3-yl methane amines) and difluorocarbene with aryl and
在无过渡金属的条件下,二氟卡宾能够实现叔胺与芳基和烯基硼酸的有效且通用的脱氨芳基化和烯基化。该协议代表了一种新的反应模式,它通过叔胺(炔丙基胺、烯丙基胺和 1H-吲哚-3-基甲烷胺)和二氟卡宾原位形成的氮叶立德成功地构建了 C sp 3 -C sp 2键与芳基和烯基硼酸。
Metal-Free and Recyclable Route to Synthesize Polysubstituted Olefins<i>via</i>CC Bond Construction from Direct Dehydrative Coupling of Alcohols or Alkenes with Alcohols Catalyzed by Sulfonic Acid-Functionalized Ionic Liquids
AbstractA direct synthesis of polysubstituted olefins via construction of CC bonds, which involves the direct dehydrative coupling of alcohols or alkenes with alcohols, was realized using a series of alkanesulfonic acid group‐functionalized ionic liquids (SO3H‐functionlization ILs) without additives. The metal‐free and recyclable catalyst system avoided the disposal and neutralization of acidic catalysts after reaction and tolerated a broad range of substrates, including benzylic, allyl, propargylic, aliphatic and aromatic or aliphatic olefins. Additionally, the catalytic system was suitable for a gram‐scale preparation. Preliminary mechanistic studies indicated that the CH bond cleavage in this reaction might be involved in the rate‐determining step.magnified image