Commercially available neat organozincs as highly reactive reagents for catalytic enantioselective addition to ketones and aldehydes under solvent free conditions
作者:Manabu Hatano、Tomokazu Mizuno、Kazuaki Ishihara
DOI:10.1016/j.tet.2011.02.042
日期:2011.6
Ph2Zn, and highly concentrated Me2Zn are highly reactive organozinc reagents, which are commercially available in bulk quantities. We here report a catalytic enantioselective Et2Zn, Ph2Zn, and Me2Zn addition to ketones and aldehydes under solventfree or highly concentrated conditions without Ti(Oi-Pr)4 as a conventional activator of organozinc reagents. The desired optically active tertiary and secondary
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
Multichannel Reaction of α-Bromoenones with 1,2-Diamines: Synthesis of 1,4-Diazabicyclo[4.1.0]hept-4-enes by Reaction with<i>N</i>-Unsubstituted 1,2-Diamines
作者:Vasily M. Muzalevskiy、Alexander Yu. Rulev、Evgeniy V. Kondrashov、Alexey R. Romanov、Igor A. Ushakov、Vyacheslav A. Chertkov、Valentine G. Nenajdenko
DOI:10.1002/ejoc.201501584
日期:2016.3
The reaction of 2-bromoenones with N-unsubstituted 1,2-diamines was studied. An easy access to 1,4-diazabicyclo[4.1.0]hept-4-enes was developed. The multistep mechanism of the reaction is discussed. Final conclusions on the influence of the structure of the starting 2-bromoenones and 1,2-diamines on the direction of the reaction are established.
Experimental and Theoretical Study of an Intramolecular CF<sub>3</sub>-Group Shift in the Reactions of α-Bromoenones with 1,2-Diamines
作者:Vasily M. Muzalevskiy、Yury A. Ustynyuk、Igor P. Gloriozov、Vyacheslav A. Chertkov、Alexander Yu. Rulev、Evgeniy V. Kondrashov、Igor A. Ushakov、Alexey R. Romanov、Valentine G. Nenajdenko
DOI:10.1002/chem.201502706
日期:2015.11.16
The reactions of trifluoromethylated 2‐bromoenones and N,N′‐dialkyl‐1,2‐diamines have been studied. Depending on the structures of the starting compounds, the formation of 2‐trifluoroacetylpiperazine or 3‐trifluoromethylpiperazine‐2‐ones was observed. The mechanism of the reaction is discussed in terms of multistep processes involving sequential substitution of bromine in the starting α‐bromoenones
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