In Situ Generation of Nucleophilic Allenes by the Gold-Catalyzed Rearrangement of Propargylic Esters for the Highly Diastereoselective Formation of Intermolecular C(sp<sup>3</sup>)C(sp<sup>2</sup>) Bonds
作者:Yang Yu、Weibo Yang、Frank Rominger、A. Stephen K. Hashmi
DOI:10.1002/anie.201302402
日期:2013.7.15
particular for the synthesis of isochromane derivatives (see scheme), are provided by the title reaction. Excellent diastereoselectivites are achieved in this reaction which proceeds through a gold‐catalyzed 1,3‐acyloxy migration. In some cases exclusively the Z isomer is detected.
Hydrogen‐Bonding‐Promoted Cascade Rearrangement Involving the Enlargement of Two Rings: Efficient Access to Polycyclic Quinoline Derivatives
作者:Wen‐Bin Cao、Shijun Li、Meng‐Meng Xu、Haiyan Li、Xiao‐Ping Xu、Yu Lan、Shun‐Jun Ji
DOI:10.1002/anie.202008110
日期:2020.11.23
An efficient cascade reaction of tryptamine‐derived isocyanides with C,N‐cyclic azomethine imines is described. The polycyclic pyrrolo[2,3‐c]quinoline derivatives, which benefited from rearrangement process driven by hydrogen bonding, could be directly assembled in moderate to good yields (40–87 %) under metal‐free and mild conditions. This transformation involved four new heterocyclic rings formations
The first asymmetric decarboxylative [4 + 3] annulation of propargylic carbamates with C, N-cyclic azomethineimines has been developed successfully by a copper- N-heterocyclic carbine system. This strategy led to a series of optically active isoquinoline-fused triazepine derivatives in good yields and with excellent enantio- and diastereoselectivities. Remarkably, Cu-allenylidene intermediates play
Synthesis of 5,6‐Dihydropyrazolo[5,1‐
<i>a</i>
]isoquinoline and Ethyl (
<i>Z</i>
)‐3‐Acetoxy‐3‐tosylpent‐4‐enoate through Tertiary‐Amine‐Catalyzed [3+2] Annulation
作者:Yu Lei、Jiao‐Jiao Xing、Qin Xu、Min Shi
DOI:10.1002/ejoc.201600577
日期:2016.7
catalyzed divergent [3+2] annulation of C,N-cyclic azomethineimines with δ-acetoxyallenoates was developed; 5,6-dihydropyrazolo[5,1-a]isoquinolines and ethyl (Z)-3-acetoxy-3-tosylpent-4-enoates were afforded in moderate to good yields in a one-pot manner under mild conditions. This annulation reaction provides a highly efficient method to construct dinitrogen-fusedheterocycles and ethyl (Z)-3-ace
Stereodivergent Anion Binding Catalysis with Molecular Motors
作者:Ruth Dorel、Ben L. Feringa
DOI:10.1002/anie.201913054
日期:2020.1.7
A photoresponsive chiral catalyst based on an oligotriazole-functionalized unidirectional molecular motor has been developed for stereodivergent anion binding catalysis. The motor function controls the helical chirality of supramolecular assemblies with chloride anions, which by means of chiralitytransfer enables the enantioselective addition of a silyl ketene acetal nucleophile to oxocarbenium cations