Synthesis of Divergent Benzo[<i>b</i>]fluorenones through Cycloaromatization Reactions of 1,5-Enynols and 1,5-Diynols
作者:Bingyu Yan、Yang Fu、Hui Zhu、Zhiyuan Chen
DOI:10.1021/acs.joc.9b00231
日期:2019.4.5
A facile and efficient synthesis of divergent benzo[b]fluorenones is described through the use of dichlorobenzoquinone-promoted oxidative cycloaromatization reactions of acyclic 1,5-enynols and 1,5-diynols. The success of these cascadereactions depends on the chemoselectivity of the initial Meyer–Schuster rearrangement to produce allenol intermediate, which is followed by regioselective Schmittel
通过使用二氯苯醌促进的无环1,5-烯醇和1,5-二炔醇的氧化环芳构化反应,描述了发散的苯并[ b ]芴酮的简便高效合成方法。这些级联反应的成功取决于初始Meyer-Schuster重排产生烯丙醇中间体的化学选择性,随后是区域选择性的Schmittel环化反应,以及随后的Friedal-Crafts烷基化反应或末端Ar部分的自由基进攻。反应中仅需要氧化剂和溶剂,因此在不含金属的条件下提供了一个小的库,具有所需的具有优异的官能团耐受性的预期多碳环产物。选定的苯并[ b]的吸收和光致发光特性还研究了芴酮。结果表明,在苯基部分包含给电子体4-OMe基团的化合物(2h)显示出深绿色发射光(491nm)。
BippyPhos: A Single Ligand With Unprecedented Scope in the Buchwald–Hartwig Amination of (Hetero)aryl Chlorides
作者:Sarah M. Crawford、Christopher B. Lavery、Mark Stradiotto
DOI:10.1002/chem.201302453
日期:2013.12.2
demonstrating the largest scope in the NH‐containing coupling partner reported for a single Pd/ligand catalyst system. We also established BippyPhos/[Pd(cinnamyl)Cl]2 as exhibiting the broadest demonstrated substrate scope for metal‐catalyzed cross‐coupling of (hetero)aryl chlorides with NH indoles. Furthermore, the remarkable ability of BippyPhos/[Pd(cinnamyl)Cl]2 to catalyze both the selective monoarylation
Intramolecular<i>anti</i>-Phosphinoauration of Alkynes: An FLP-Motivated Approach to Stable Aurated Phosphindolium Complexes
作者:Sebastian Arndt、Max M. Hansmann、Petr Motloch、Matthias Rudolph、Frank Rominger、A. Stephen K. Hashmi
DOI:10.1002/chem.201605914
日期:2017.2.21
elevated temperatures induced the cyclization to give stable aurated phosphindolium salts, which is supported by DFT calculations. The key elementary step that comprises a yet unknown anti‐phosphinoauration of an unactivated alkyne is favored if bulky NHC ligands are used which was analyzed by kinetic measurements. This concept could furthermore be extended to neutral (phosphindolium)AuCl complexes featuring
Application of Isocyanides as Amide Surrogates in the Synthesis of Diverse Isoindolin-1-one Derivatives by a Palladium-Catalyzed Tandem Carboxamidation/Hydroamidation Reaction
作者:Ramdas S Pathare、Shivani Sharma、Sathish Elagandhula、Vaishali Saini、Devesh M Sawant、Monika Yadav、Ashoke Sharon、Shahnawaz Khan、Ram T Pardasani
DOI:10.1002/ejoc.201600999
日期:2016.11
The rapid synthesis of the isoindolinone skeleton has been accomplished by a palladium-catalyzed one-pot tandem process, which consists of an isocyanideinsertion/hydration (carboxamidation) and 5-exo-dig cycloisomerization (hydroamidation) reaction sequence that afforded the products in good to excellent yields. Preliminary mechanistic studies of this sequential C–C/C–O/C–N bond formation process
DDQ-Mediated Oxidative Radical Cycloisomerization of 1,5-Diynols: Regioselective Synthesis of Benzo[<i>b</i>]fluorenones under Metal-Free Conditions
作者:Hui Zhu、Zhiyuan Chen
DOI:10.1021/acs.orglett.5b03533
日期:2016.2.5
has been developed. The reaction proceeds under metal-free reaction conditions with high efficiency and broad functional group tolerance, which offers a general and straightforward access to benzo[b]fluorenones under metal-free conditions. The preliminary mechanistic studies revealed the possible involvement of a Meyer–Schuster rearrangement combined with an oxidative radical cyclization.
已经开发了无环1,5-二炔醇的区域和化学选择性氧化环异构化反应。该反应在无金属的反应条件下进行,具有较高的效率和宽泛的官能团耐受性,这为在无金属的条件下提供一般直接的苯并[ b ]芴酮的途径。初步的机理研究表明,梅尔-舒斯特重排与氧化自由基环化相结合的可能性。