Ruthenium-Catalyzed Transfer Oxygenative Cyclization of α,ω-Diynes: Unprecedented [2 + 2 + 1] Route to Bicyclic Furans via Ruthenacyclopentatriene
摘要:
A novel oxygen-atom-transfer process enables the catalytic [2 + 2 + 1] synthesis of bicyclic furans from alpha,omega-diynes with DMSO. [CpRu(AN)(3)]PF6 catalyzed the transfer oxygenative cyclization of diynes with aryl terminal groups, while those of diynes with alkyl terminal groups were effectively promoted by the corresponding Cp* complex. A mechanism for bicyclic furan formation via a ruthenacyclopentatriene was proposed on the basis of both experimental and theoretical studies.
Enabling the Use of Alkyl Thianthrenium Salts in Cross‐Coupling Reactions by Copper Catalysis
作者:Cheng Chen、Minyan Wang、Hongjian Lu、Binlin Zhao、Zhuangzhi Shi
DOI:10.1002/anie.202109723
日期:2021.9.27
used groups in organic synthesis. Here, a a series of thianthreniumsalts have been synthesized that act as reliable alkylation reagents and readily engage in copper-catalyzed Sonogashira reactions to build C(sp3)−C(sp) bonds under mild photochemical conditions. Diverse alkyl thianthreniumsalts, including methyl and disubstituted thianthreniumsalts, are employed with great functional breadth, since
Nickel(0)-mediated [2+2+1] cyclization reaction of chromium carbene complexes and internal alkynes
作者:José Barluenga、Pablo Barrio、Lorena Riesgo、Luis A. López、Miguel Tomás
DOI:10.1016/j.tet.2006.03.117
日期:2006.8
heteroaryl chromiumFischercarbenecomplexes undergo Ni(0)-mediated [2+2+1] cyclizationreaction with internal unactivated and electron-poor internal alkynes to yield highly substituted cyclopentadienes with complete regioselectivity in most cases. The intramolecular version of this cyclization has been accomplished with 1,8-diphenyl-1,7-octadiyne to produce indene derivatives. This three-component [2+2+1]
A simple and efficient synthesis of cyclopentadienones via palladium-catalyzed cyclocarbonylation of alkynes under atmosphericpressure of carbonmonoxide has been developed. The transformation was carried out under mild and ligand-free conditions, a wide range of substrates and exceptional functional group tolerance.
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
Use of (Cyclopentadienone)iron Tricarbonyl Complexes for C–N Bond Formation Reactions between Amines and Alcohols
作者:Thomas J. Brown、Madeleine Cumbes、Louis J. Diorazio、Guy J. Clarkson、Martin Wills
DOI:10.1021/acs.joc.7b01990
日期:2017.10.6
of a series of (cyclopentadienone)iron tricarbonyl complexes to “borrowing hydrogen” reactionsbetweenamines and alcohols was completed in order to assess their catalytic activity. The electronic variation of the aromatic groups flanking the C═O of the cyclopentadienone influenced the efficiency of the reactions; however, in other cases, the Knölker catalyst 1, containing trimethylsilyl groups flanking