多环芳烃 (PAH),例如苯并 [ a ] 芘 (B a P),是普遍存在的环境污染物,与导致肺癌有关。B a P 是烟草烟雾的一种成分,通过酶促转化为与 DNA 相互作用的活性形式。我们之前报道了一种用于分析 B a P 代谢物的灵敏的稳定同位素稀释 LC/MS 方法的开发。我们现在报告了13 C 4 -B a P 的有效合成及其完整的13 C 4标记氧化代谢物,需要作为内标。它们包括不参与致癌作用的代谢物(A 组))和与癌症发生有关的代谢物(B组)。该合成方法是新颖的,需要使用 Pd 催化的 Suzuki、Sonogashira 和 Hartwig 交叉偶联反应与 PtCl 2催化的炔属化合物环化反应相结合。这种合成方法需要更少的步骤,使用更温和的条件,并且产物分离比传统的 PAH 合成方法更简单。13 C 4 -B a P 和13 C 4 -B a P-8-ol的合成各只需要四步,并且13
Novel Selective Approach to Terminally Substituted [<i>n</i>
]Dendralenes
作者:Peter Polák、Tomáš Tobrman
DOI:10.1002/ejoc.201801522
日期:2019.2.7
A methodology for the synthesis of terminally substituted [3]‐ and [4]dendralenes, as well as 2,3‐disubstituted buta‐1,3‐dienes has been prepared. This involves the preparation of 1,2‐disubstituted cyclobutenes from readily available 2‐bromocyclobutanone and the subsequent thermal ring‐opening reactions.
Direct Vinylation and Difluorovinylation of Arylboronic Acids Using Vinyl- and 2,2-Difluorovinyl Tosylates via the Suzuki−Miyaura Cross Coupling
作者:Thomas M. Gøgsig、Lina S. Søbjerg、Anders T. Lindhardt、Kim L. Jensen、Troels Skrydstrup
DOI:10.1021/jo7027097
日期:2008.5.1
reaction conditions were developed for the Pd(0)-catalyzed Suzuki−Miyaura coupling reaction of aryl boronic acids with a simple electrophilic vinylation reagent, vinyl tosylate, providing access to styrene derivatives in good yields. The easilyaccessible vinyl tosylate represents a stable and less toxic alternative to the vinyl halides and the triflate/nonaflate derivatives. Furthermore, this methodology
Decarboxylative Benzylation of Aryl and Alkenyl Boronic Esters
作者:Patrick J. Moon、Anis Fahandej‐Sadi、Wenyu Qian、Rylan J. Lundgren
DOI:10.1002/anie.201800829
日期:2018.4.16
The copper‐catalyzed decarboxylative benzylation of aryl and alkenyl boronicesters with electron‐deficient aryl acetates is reported. The oxidative coupling proceeds under mild, aerobic conditions and tolerates a host of potentially reactive electrophilic functional groups that would be problematic with traditional benzylation methods (aryl iodides and bromides, protic heteroatoms, aldehydes, Michael
A Nickel Catalyst for the Addition of Organoboronate Esters to Ketones and Aldehydes
作者:Jean Bouffard、Kenichiro Itami
DOI:10.1021/ol9017613
日期:2009.10.1
Ni(cod)2/IPr catalyst promotes the intermolecular 1,2-addition of arylboronate esters to unactivated aldehydes and ketones. Diaryl, alkyl aryl, and dialkyl ketones show good reactivity under mild reaction conditions (≤80 °C, nonpolar solvents, no strong base or acid additives). A dramatic ligand effect favors either carbonyl addition (IPr) or C−OR cross-coupling (PCy3) with aryl ether substrates. A Ni(0)/Ni(II)
Nickel‐Catalyzed Regioselective Alkenylarylation of γ,δ‐Alkenyl Ketones via Carbonyl Coordination
作者:Roshan K. Dhungana、Vivek Aryal、Doleshwar Niroula、Rishi R. Sapkota、Margaret G. Lakomy、Ramesh Giri
DOI:10.1002/anie.202104871
日期:2021.8.23
which enabled us to difunctionalize unactivated γ,δ-alkenes in ketones with alkenyl triflates and arylboronic esters. The reaction was made feasible by the use of 5-chloro-8-hydroxyquinoline as a ligand along with NiBr2⋅DME as a catalyst and LiOtBu as base. The reaction proceeded with a wide range of cyclic, acyclic, endocyclic and exocyclic alkenylketones, and electron-rich and electron-deficient arylboronate
我们公开了镍催化的反应,该反应使我们能够用三氟甲磺酸烯基酯和芳基硼酸酯对酮中未活化的γ,δ-烯烃进行双官能化。通过使用 5-氯-8-羟基喹啉作为配体以及 NiBr 2· DME 作为催化剂和 LiO t Bu 作为碱,使该反应变得可行。该反应适用于各种环状、无环、环内和环外烯基酮,以及富电子和缺电子芳基硼酸酯。该反应也适用于环状和无环烯基三氟甲磺酸酯。对照实验表明反应的进行需要羰基配位。