Room Temperature Carbonylation of (Hetero) Aryl Pentafluorobenzenesulfonates and Triflates using Palladium-Cobalt Bimetallic Catalyst: Dual Role of Cobalt Carbonyl
作者:Jayan T. Joseph、Ayyiliath M. Sajith、Revanna C. Ningegowda、Sheena Shashikanth
DOI:10.1002/adsc.201600736
日期:2017.2.2
method for the carbonylation of (hetero) aryl pentafluorobenzenesulfonates and triflates under exceptionally mild conditions using palladium/dicobalt octacarbonyl [Pd/Co2(CO)8] has been developed. Besides acting as carbon monoxide (CO) source, Co2(CO)8 enhances the reaction rate by accelerating the CO insertion through an in situ generated bimetallic palladium cobalt tetracarbonyl [Pd‐Co(CO)4] complex
已经开发了一种在异常温和的条件下使用钯/二钴八羰基[Pd / Co 2(CO)8 ]对(杂)芳基五氟苯磺酸盐和三氟甲磺酸酯进行羰基化的有效方法。除了充当一氧化碳(CO)源外,Co 2(CO)8还可以通过原位生成的双金属钯四羰基钴[Pd-Co(CO)4)加速CO的插入,从而提高反应速率。] 复杂的。在优化的反应条件下,各种活化和失活的,以及位阻和杂芳族底物的羰基化反应在室温下均能有效进行。生物学上相关的异古瓦汀和拉扎贝米中间体的高化学选择性和改进的合成方法突出了其作为有价值的合成方法的范围。该协议的通用性进一步扩展到其他亲电试剂(溴化物,氯化物和甲苯磺酸盐)。
InCl<sub>3</sub>-Catalyzed Synthesis of 1,2-Dimetallic Compounds by Direct Insertion of Aluminum or Zinc Powder
作者:Tobias D. Blümke、Thomas Klatt、Konrad Koszinowski、Paul Knochel
DOI:10.1002/anie.201205169
日期:2012.9.24
In‐sertion of metal: Catalytic amounts of InCl3 allow the insertion of aluminum and zinc into aromatic 1,2‐dibromides or 1,2‐bromotriflates (see scheme). These 1,2‐dimetallic species can undergo Cu or Pd‐catalyzed acylations, allylations, or cross‐couplings.
Formation of 1-Benzosuberones by Three-Carbon Ring Expansion of Benzocylobutenones<sup>1</sup>
作者:Wei Zhang、Rudiger Gomy、Paul Dowd
DOI:10.1080/00397919908086459
日期:1999.8
Abstract A new method for preparing 1-benzosuberone derivatives by free radical promoted three-carbonringexpansion of benzocyclobutenones is described.
摘要 介绍了一种利用自由基促进苯并环丁烯酮的三碳扩环制备1-苯并丁烯酮衍生物的新方法。
Construction of Functionalized <i>ortho</i>‐Naphthoquinone Methides via Site‐Selective Ring Opening of 1‐Siloxy‐1,4‐epoxy‐1,4‐dihydronaphthalenes
underwent automatic site-selective ringopening because of the synergetic effect of the steric strain of the 1,4-epoxy moiety and the electron-donating ability of the siloxy group on the acetal structure to afford the precursors of ortho-naphthoquinone methides (o-NQMs). Subsequent Lewis acid-facilitated o-NQM formation and annulation with olefins afforded multi-fused heterocycles. Notably, the consecutive
由苯炔和呋喃生成的1-甲硅烷氧基-4-(苄氧基)甲基-1,4-环氧-1,4-二氢萘由于1,4空间张力的协同作用而自动进行位点选择性开环-环氧部分和缩醛结构上甲硅烷氧基的给电子能力,提供邻萘醌甲基化物(o -NQMs)的前体。随后路易斯酸促进邻-NQM 形成并与烯烃成环,得到多稠合杂环。值得注意的是,rubioncolin B 的连续六环骨架是通过萘并呋喃衍生物的溶剂依赖性区域选择性成环构建的。
Aryl bromide/triflate selectivities reveal mechanistic divergence in palladium-catalysed couplings; the Suzuki–Miyaura anomaly
作者:Gustavo Espino、Almira Kurbangalieva、John M. Brown
DOI:10.1039/b701517h
日期:——
In palladium-catalysed cross-coupling reactions, the outcome of competition between aryl bromides and aryl triflates depends on the nucleophilic partner; Suzuki couplings with RâB generally follow a different pattern from other RâM species.