“Bulky-Yet-Flexible” α-Diimine Palladium-Catalyzed Reductive Heck Cross-Coupling: Highly Anti-Markovnikov-Selective Hydroarylation of Alkene in Air
作者:Xu-Wen Yang、Dong-Hui Li、A-Xiang Song、Feng-Shou Liu
DOI:10.1021/acs.joc.0c01509
日期:2020.9.18
regioselective and efficient reductive Heck reaction, a series of moisture- and air-stable α-diimine palladium precatalysts were rationally designed, readily synthesized, and fully characterized. The relationship between the structures of the palladiumcomplexes and the catalytic properties was investigated. It was revealed that the“bulky-yet-flexible”palladiumcomplexes allowed highly anti-Markovnikov-selective
Approaches to 1<i>H</i>-Cyclopropa[<i>l</i>]phenanthrenes. Eliminations with 1a,9b-Dihydro-1<i>H</i>-cyclopropa[<i>l</i>]phenanthrene Derivatives
作者:Paul Müller、Huong Can Nguyen Thi、Jean Pfyffer
DOI:10.1002/hlca.19860690412
日期:1986.6.18
Base-induced elimination of the sulfonium salt 2i in the presence of furan affords the addition products 7 and 8, derived from 1H-cyclopropa[l]phenanthrene (1) and the isomeric cyclopropene 5a(Scheme 3). Upon oxidation, the selenide 2c yields phenanthrene-9-methanol (9), presumably via1. No evidence for the intermediate 1 is obtained from sulfoxide pyrolysis with 2e, which leads to products formed
An efficient method for the synthesis of industrially important dibenzyls and alkyl phenyl esters via sequential Heck coupling and hydrogenation of the alkenyl double bond in one pot with a single recyclable catalyst under mild conditions has been realised. The catalyst was recovered by simple filteration and reused for several cycles with consistent activity.
Phenanthrene Synthesis by Eosin Y-Catalyzed, Visible Light- Induced [4+2] Benzannulation of Biaryldiazonium Salts with Alkynes
作者:Tiebo Xiao、Xichang Dong、Yanchi Tang、Lei Zhou
DOI:10.1002/adsc.201200569
日期:2012.11.26
A metal-free, visible light-induced [4+2] benzannulation of biaryldiazonium salts with alkynes was developed. With eosin Y as photoredox catalyst, a variety of 9-substituted or 9,10-disubstitutedphenanthrenes were obtained via a cascade radical addition and cyclization sequence.
Oxidative, Iodoarene‐Catalyzed Intramolecular Alkene Arylation for the Synthesis of Polycyclic Aromatic Hydrocarbons
作者:Zhensheng Zhao、Liam H. Britt、Graham K. Murphy
DOI:10.1002/chem.201804786
日期:2018.11.16
metal‐free and chemoselective oxidative intramolecular coupling of arene and alkene C−H bonds is reported. The active hypervalent iodine (HVI) reagent, generated catalytically in situ from iodotoluene and meta‐chloroperoxybenzoic acid (m‐CPBA), reacts with o‐vinylbiphenyls to generate polyaromatic hydrocarbons in up to 95 % yield. Experimental evidence suggests the reactions proceed though vinyliodonium