Diboration of 3-substituted propargylic alcohols using a bimetallic catalyst system: access to (<i>Z</i>)-allyl, vinyldiboronates
作者:Cheryl L. Peck、Jan Nekvinda、Webster L. Santos
DOI:10.1039/d0cc03563g
日期:——
A Pd/Cu catalyst system facilitates the diboration of unactivated propargylic alcohols with pentafluoroboronic acid and diboron to generate (Z)-allyl, vinyldiboronates.
Palladium-Catalyzed [5 + 1] Annulation of Salicylic Acid Derivatives and Propargylic Carbonates
作者:Kazuya Sato、Yohei Ogiwara、Norio Sakai
DOI:10.1246/bcsj.20200199
日期:2020.12.15
A palladium-catalyzed annulation reaction between salicylicacid derivatives and propargylic carbonates via the cleavage of a propargylic carbon–oxygen bond is described. This rare annulation react...
synthesis of new core-Au/shell-CeO2 nanoparticles (Au@CeO2) using a redox-coprecipitation method, where the Au nanoparticles and the nanoporous shell of CeO2 are simultaneously formed in one step. The Au@CeO2catalyst enables the highly selective semihydrogenation of various alkynes at ambient temperature under additive-free conditions. The core-shellstructure plays a crucial role in providing the excellent
我们报告了一种使用氧化还原共沉淀法轻松合成新的核-Au/壳-CeO2 纳米颗粒(Au@CeO2),其中 Au 纳米颗粒和 CeO2 的纳米多孔壳在一个步骤中同时形成。Au@CeO2 催化剂能够在无添加剂的条件下在环境温度下实现各种炔烃的高选择性半氢化。核-壳结构通过最大化核-Au 和壳-CeO2 之间的界面位点,以异裂方式选择性解离 H2,从而为烯烃提供优异的选择性。
Heterocyclic pesticidal compounds
申请人:The Wellcome Foundation
公开号:US05502073A1
公开(公告)日:1996-03-26
Compounds of the formula (I) ##STR1## which contain between 10 and 27 carbon atoms, and wherein m and n are independently selected from 0, 1 and 2; R.sup.2a is hydrogen, methyl, or ethyl; R.sup.2b is acetylene or contains between 3 and 18 carbon atoms and is a group R.sup.7, wherein R.sup.7 is a C.sub.1-13 non-aromatic hydrocarbyl group, optionally substituted by a cyano or C.sub.1-4 carbalkoxy group and/or by one or two hydroxy groups and/or by one to five halo atoms which are the same or different and/or by one to three groups R.sup.8 which are the same or different and each contain one to four hetero atoms, which are the same or different and are chosen from oxygen, sulphur, nitrogen and silicon, 1 to 10 carbon atoms and optionally 1 to 6 fluoro or chloro atoms or R.sup.2b is a 6-membered aromatic ring substituted by cyano and/or by one to three groups R.sup.8 and/or by a group --C.tbd.CH, --C.tbd.C-R.sup.7 or C.tbd.C-halo and/or by one to five halo atoms and/or by one to three C.sub.1-4 haloalkyl groups wherein R.sup.7 and R.sup.8 are as hereinbefore defined; R.sup.4 and R.sup.6 are the same or different and are chosen from hydrogen, methyl, trifluoromethyl or cyano; and R.sup.5 is hydrogen or methyl provided that R.sup.2b is not propyl or butyl are described which have pesticidal activity, particularly against arthropod pests. Pesticidal formulations containing the compounds of the formula (I), their use in the control of pests and method for their preparation are also disclosed.
Intramolecular Imino Diels−Alder Reaction: Progress toward the Synthesis of Uncialamycin
作者:Sandy Desrat、Pierre van de Weghe
DOI:10.1021/jo901291t
日期:2009.9.4
We herein described an intramoleculariminoDiels−Alderreaction promoted with BF3·OEt2/DDQ affording substituted quinolines. Using this procedure, we prepared the chiral quinoline moiety of the uncialamycin, a new enediyne natural product.