Silver-Catalyzed Isocyanide-Alkyne Cycloaddition: A General and Practical Method to Oligosubstituted Pyrroles
作者:Jianquan Liu、Zhongxue Fang、Qian Zhang、Qun Liu、Xihe Bi
DOI:10.1002/anie.201302024
日期:2013.7.1
key: The transition‐metal‐catalyzed cycloaddition of isocyanides and unactivated terminal alkynes has been realized with Ag2CO3 as a unique and robust catalyst (see scheme). The protocol is highly efficient, allowing a broad range of terminal and internal alkynes to react under base‐ and ligand‐free conditions, generating synthetically useful oligosubstitutedpyrroles in high yields.
Ag 2 CO 3是关键:Ag 2 CO 3是一种独特而坚固的催化剂,已经实现了过渡金属催化的异氰酸酯和未活化的末端炔烃的环加成反应(参见方案)。该方案非常高效,可以使各种末端和内部炔烃在无碱和无配体的条件下反应,从而以高收率生成合成上有用的寡取代吡咯。
Consecutive O−S/N−S Bond Cleavage in Gold‐Catalyzed Rearrangement Reactions of Alkynyl
<i>N</i>
‐Sulfinylimines
作者:Hiroki Tashiro、Masahiro Terada、Itaru Nakamura
DOI:10.1002/anie.202100207
日期:2021.5.25
corresponding 2H‐azirines possessing sulfenyl and acyl groups at the 3‐position of the azirine ring in good to excellent yields. These reactions involved internal transfer of the sulfinyl oxygen atom to form a thiooxime intermediate tethered to an α‐oxo gold carbene moiety. Subsequent insertion of the carbene into the N−S bond resulted in ringconstruction.
Pd-Catalyzed Carbonylative Reactions of Aryl Iodides and Alkynyl Carboxylic Acids via Decarboxylative Couplings
作者:Ahbyeol Park、Kyungho Park、Yong Kim、Sunwoo Lee
DOI:10.1021/ol102993y
日期:2011.3.4
carboxylic acids reacted with aryliodides under a CO atmosphere in the presence of a palladium catalyst to produce α,β-alkynyl aryl ketones in good yields. The maximum turnover number was 16 800. The desired carbonylativecoupling was formed from phenyl propiolic acid without any formation of a noncarbonylative coupling product in the absence of CuI. However, the reaction with alkyl-substituted alkynyl
PPh<sub>3</sub>-KOBu<sup>t</sup>–Mediated Cyclization Reaction of <font>β</font>-Ketoesters with Alkynyl Ketones: Synthesis of Functionalized 2-Pyrones
Abstract Cyclization of alkynyl ketones with β-ketoesters mediated by PPh3 and KOBut to synthesize 2-pyrone derivatives was systematically described. A variety of β-ketoesters reacted with alkynyl ketones to give functionalized 2-pyrones in moderate to good yields under mild conditions.
A novel and efficient approach for the synthesis of functionalized isoxazoles viapalladium-catalyzed cascade annulation/allylation of alkynyl oxime ethers with allyl halides has been established. The present protocol exhibits mild reaction conditions, good functional group compatibility, and convenient operation. Moreover, scalability was performed and further decoration of the isoxazole product was