A concisetotalsynthesis of (-)-muricatacin and (-)- ISO-cladospolide B has been achieved by using chemoselective cross-metatheses and asymmetric dihydroxylations. These key reactions allow a fast access to α-hydroxybutyrolactones.
通过使用化学选择性交叉复分解和不对称二羟基化,已经实现了 (-)-muricatacin 和 (-)- ISO-cladospolide B 的简明全合成。这些关键反应可以快速获得 α-羟基丁内酯。
Synthesis of Naturally Occurring Acetylenes via an Alkylidene Carbenoid Rearrangement
作者:Annabelle L. K. Shi Shun、Rik R. Tykwinski
DOI:10.1021/jo034734g
日期:2003.8.1
Naturallyoccurring mosquito larvicidal acetylenes 1 and 2, and analogues 3 and 4, each containing either a 1,3-butadiynyl or a 1,3,5-hexatriynyl moiety, are synthesized via a Fritsch-Buttenberg-Wiechell rearrangement. The alkylidene carbenoid intermediate results from lithium-halogen exchange of a suitable dibromoolefin precursor, and the rearrangement is accomplished under mild conditions. Synthesis
3‐Oxo‐5‐alkynoic acid esters, on treatment with a carbophilic catalyst, undergo 6‐endo‐digcyclizationreactions to furnish either 2‐pyrones or 4‐pyrones in high yields. The regiochemical course can be dialed in by the proper choice of the alcohol part of the ester and the π‐acid. This transformation is compatible with a variety of acid‐sensitive groups as witnessed by a number of exigent applications
Hetero-Tetradehydro-Diels–Alder Cycloaddition of Enynamides and Cyanamides: Gold-Catalyzed Generation of Diversely Substituted 2,6-Diaminopyridines
作者:Nikolay V. Shcherbakov、Dmitry V. Dar’in、Vadim Yu. Kukushkin、Alexey Yu. Dubovtsev
DOI:10.1021/acs.joc.1c00558
日期:2021.5.21
hetero-tetradehydro-Diels–Alder cycloaddition of enynamides and cyanamides comprises an efficient route to diversely substituted 2,6-diaminopyridines (28 examples; yields up to 99%). The reaction proceeds under very mild conditions (DCM, rt) with high functional group tolerance. The obtained 2,6-diaminopyridines represent a useful synthetic platform with an easily modulated substitution pattern for subsequent
Chemoselective Construction of Substituted Conjugated Dienes Using an Olefin Cross-Metathesis Protocol
作者:Timothy W. Funk、Jon Efskind、Robert H. Grubbs
DOI:10.1021/ol047929z
日期:2005.1.1
[Reaction: see text] Various substituted conjugateddienes have been made by olefin cross-metathesis. Using either electronic or steric "protection," one of the olefins of the conjugateddiene was deactivated relative to the other for cross-metathesis. The reactions proceed with very high chemoselectivity and, when steric deactivation is used, very high diastereoselectivity.