Gold(I)‐Catalyzed Highly Diastereo‐ and Enantioselective Cyclization–[4+3] Annulation Cascades between 2‐(1‐Alkynyl)‐2‐alken‐1‐ones and Anthranils
作者:Rahul Dadabhau Kardile、Tzu‐Hsuan Chao、Mu‐Jeng Cheng、Rai‐Shung Liu
DOI:10.1002/anie.202001854
日期:2020.6.22
This work reports gold‐catalyzed [4+3]‐annulations of 2‐(1‐alkynyl)‐2‐alken‐1‐ones with anthranils to yield epoxybenzoazepine products with excellent exo ‐diastereoselectivity (dr>25:1). The utility of this new gold catalysis is manifested by applicable substrates over a broad scope. More importantly, the enantioselective versions of these [4+3]‐cycloadditions have been developed satisfactorily with
A CONVENIENT METHOD FOR THE DIRECT PREPARATION OF KETONES FROM 2-(6-(2-METHOXYETHYL)PYRIDYL)CARBOXYLATES AND ALKYL IODIDES BY USE OF ZINC DUST AND A CATALYTIC AMOUNT OF NICKEL DICHLORIDE
作者:Makoto Onaka、Yoshio Matsuoka、Teruaki Mukaiyama
DOI:10.1246/cl.1981.531
日期:1981.4.5
Treatment of 2-(6-(2-methoxyethyl)pyridyl) carboxylates with alkyl iodides in the presence of zinc dust and a catalytic amount of NiCl2 in DMF at 50 °C affords unsymmetrical ketones in good yields by a one-pot procedure.
在锌粉和催化量的 NiCl2 的 DMF 存在下,在 50 °C 下用烷基碘处理 2-(6-(2-甲氧基乙基)吡啶基)羧酸酯,通过一锅法以良好的收率提供不对称酮。
One-Pot Consecutive Reactions Based on the Synthesis of Conjugated Enones by the Re-Catalysed Meyer-Schuster Rearrangement
Re catalysis in one‐pot reactions: An atom‐economical, one‐pot strategy that involves alkyne deprotonation and a subsequent rhenium(V)‐catalysed Meyer–Schuster rearrangement of the alkynol to provide α,ß‐unsaturated enones in high yield has been developed (see scheme). Subsequent in situ hydride reduction or Diels–Alder reaction of the enones provided products in good‐to‐high overall yields.
Gold(I)-Catalyzed Reactions between 2-(1-Alkynyl)-2-alken-1-ones and Vinyldiazo Ketones for Divergent Synthesis of Nonsymmetric Heteroaryl-Substituted Triarylmethanes: <i>N-</i> versus <i>C</i>-Attack Paths
作者:Rahul Dadabhau Kardile、Rai-Shung Liu
DOI:10.1021/acs.orglett.0c02765
日期:2020.11.6
Gold-catalyzed synthesis of nonsymmetrical heteroaryl-substitutedtriarylmethanes using 2-(1-alkynyl)-2-alken-1-ones and vinyldiazo ketones is described. In this catalytic sequence, vinyldiazo ketones attack gold-containing 3-furylbenzyl cations to form the observed C(1)-addition products. We also note that vinyldiazo ketones can be thermally cyclized to yield pyrazole derivatives, which can react