Efficient Assembly of the Phomactin Core via Two Different Macrocyclization Protocols
摘要:
[GRAPHICS]The core structure of phomactins C and D was assembled by an efficient strategy starting from 3,4-dimethylcyclohexen-2-one. Key reactions include (1) a high yielding and highly diastereoselective Michael addition of a mixed cuprate, (2) a carbonylative alkyne-enoltriflate coupling or an intramolecular addition of an acetylide onto an aldehyde to form the macrocycle, (3) chemoselective Michael addition of a cuprate to an enynone, to give the carbon framework of desformyl phomactin C or D, and finally (4) regioselective addition of a thia-nucleophile to the more reactive beta -position of the resulting dienone.
Synthesis of [6,6,m]-Tricyclic Compounds via [4+2] Cycloaddition with Au or Cu Catalyst
作者:Chang Ho Oh、Juyeon Kang、Seunghwan Ham、Chaehyeon Seong
DOI:10.1055/a-1479-6005
日期:2021.6
We synthesized [6,6,6]- and [6,6,7]-tricyclic compounds via intramolecular [4+2] cycloaddition by gold or copper catalysts. Substrates for cyclization were prepared by coupling reactions between eight types of diyne and four types of aromatic moieties. We have successfully synthesized eleven tricyclic compounds.
Natural acetylenes. Part XL. Syntheses of polyacetylenic C18 and C16 esters with 9-ene-12,14-diyne unsaturation, and their labelling
作者:Alexander G. Fallis、Milton T. W. Hearn、Ewart R. H. Jones、Viktor Thaller、John L. Turner
DOI:10.1039/p19730000743
日期:——
The esters R[CC]2·CH2CH[graphics omitted]CH·[CH2]7·CO2MeR = Me[CH2]2, MeCC, cis- or trans-MeCHCH, trans-HO·CH2·CHCH, HO·CH2·CC, cis- or trans-MeO2C·CHCH, MeO2C·CC, (EtO)2CH, OHC, or, H2N·OC} were prepared from the Wittig salt Me3Si·CC·CH2·CH2·PPh3I–via ICC·CH2·CH[graphics omitted]CH·[CH2]7·CO2Me; several were specifically labelled [at C(9), C(17), and C(18)]. The Wittig salt offers a general route
Regiospecific Synthesis of the C and D Rings of Viridin
作者:Brian Keay、Kristine Muller
DOI:10.1055/s-2008-1072651
日期:2008.5
An eight-step regiospecificsynthesis of the C and D rings of viridin is reported using an intramolecular Diels-Alder reaction of a furan diene as the key step.
使用呋喃二烯的分子内 Diels-Alder 反应作为关键步骤,报道了绿色素的 C 和 D 环的八步区域特异性合成。
Copper-Catalyzed Oxy-Alkynylation of Diazo Compounds with Hypervalent Iodine Reagents
作者:Durga Prasad Hari、Jerome Waser
DOI:10.1021/jacs.6b00278
日期:2016.2.24
Alkynes have found widespread applications in synthetic chemistry, biology, and materials sciences. In recent years, methods based on electrophilic alkynylation with hypervalent iodine reagents have made acetylene synthesis more flexible and efficient, but they lead to the formation of one equivalent of an iodoarene as side-product. Herein, a more efficient strategy involving a copper-catalyzed oxy-alkynylation