Stereoselective access to substituted enediyne building blocks
摘要:
Intermolecular coupling-elimination of disubstituted propargyl bromides gives rise to differentially substituted 3-hexen-1,5-diynes with E:Z selectivity as high as 100:1. Application of the methodology in the synthesis of key nanomaterial building blocks is demonstrated. (C) 1999 Elsevier Science Ltd. All rights reserved.
A Direct and Stereocontrolled Route to Conjugated Enediynes
作者:Graham B. Jones、Justin M. Wright、Gary W. Plourde、George Hynd、Robert S. Huber、Jude E. Mathews
DOI:10.1021/ja993766b
日期:2000.3.1
A unified synthetic route to 3-hex-en-1,5-diynes, a key building block found in many of the enediyne antitumor agents and designed materials, was developed. The method, which relies on a carbenoid coupling-elimination strategy is tolerant of a wide range of functionalities, and was applied to the synthesis of a variety of linear and cyclic enediynes. Reaction parameters can be adjusted to control stereoselectivity
Nickel-Catalyzed Asymmetric Cross-Couplings of Racemic Propargylic Halides with Arylzinc Reagents
作者:Sean W. Smith、Gregory C. Fu
DOI:10.1021/ja805165y
日期:2008.9.24
A stereoconvergent method for the catalyticasymmetric Negishi cross-coupling of racemic secondary propargylic halides with arylzincreagents has been developed. Neither family of compounds has previously been shown to be a suitable partner in such coupling processes. From a practical point of view, it is noteworthy that the catalyst components (NiCl2.glyme and pybox ligand 1) are commercially available
Catalytic Enantioconvergent Allenylation of Aldehydes with Propargyl Halides
作者:Feng‐Hua Zhang、Xiaochong Guo、Xianrong Zeng、Zhaobin Wang
DOI:10.1002/anie.202117114
日期:2022.3
A Cr-catalyzed enantioconvergent allenylation reaction of aldehydes with racemic propargyl halides has been developed. This robust method employs simple and readily accessible materials, exhibits exceptional functional group tolerance and broad substrate scope, and provides facile access to a wide range of valuable optically enriched α-allenols with two or three continuous chiral centers, including
Design of Hemilabile N,N,N-Ligands in Copper-Catalyzed Enantioconvergent Radical Cross-Coupling of Benzyl/Propargyl Halides with Alkenylboronate Esters
halides with alkenylboronate esters is an appealing tool in the assembly of synthetically valuable enantioenriched alkenes owing to the ready availability, low toxicity, and air/moisture stability of alkenylboronate esters. Here, we report a copper/chiral N,N,N-ligand catalytic system for the enantioconvergent cross-coupling of benzyl/propargyl halides with alkenylboronate esters (>80 examples) with good