Expeditious synthesis of fluorinated styrylbenzenes and polyaromatic hydrocarbons
摘要:
A series of fluorinated styrylbenzene derivatives were synthesized by the Mizoroki-Heck reaction using phosphine-free catalytic conditions or by adopting the one-pot Wittig-Heck reaction sequence. The fluorinated styrylbenzenes were converted into polyaromatic hydrocarbons such as phenanthrenes, [4]helicenes, and benzo[ghi]perylene by a modified photocyclization procedure involving I-2-THF condition. (C) 2012 Elsevier Ltd. All rights reserved.
Synthesis of stilbene analogues by one-pot oxidation-Wittig and oxidation-Wittig–Heck reaction
作者:Akeel S. Saiyed、Krupa N. Patel、Bola V. Kamath、Ashutosh V. Bedekar
DOI:10.1016/j.tetlet.2012.06.090
日期:2012.8
Synthesis of symmetrical (and unsymmetrical) stilbene derivatives is achieved by a combination of one-pot steps of Kornblum type oxidation of benzyl halide, its simultaneous in situ formation of phosphonium salt, and subsequently their Wittig reaction. In other variant it is oxidized to aldehyde, treated with ylide generated from phosphonium salt (CH3PPh3X) to give styrene, and subjected to Pd catalyzed
decarbonylative alkenylation of aromatic carboxylic acids was developed. Under the reaction conditions, various benzoic acids including those bearing functional groups coupled to terminal alkenes, producing the corresponding internal alkenes in good to high yields. Cinnamic acids and bioactive benzoic acids such as 3-methylflavone-8-carboxylic acid, probenecid, adapalin, and febuxostat were also applicable to this
An Interrupted Pummerer/Nickel-Catalysed Cross-Coupling Sequence
作者:Miles H. Aukland、Fabien J. T. Talbot、José A. Fernández-Salas、Matthew Ball、Alexander P. Pulis、David J. Procter
DOI:10.1002/anie.201805396
日期:2018.7.26
An interrupted Pummerer/nickel‐catalysedcross‐coupling strategy has been developed and used in the elaboration of styrenes. The operationally simple method can be carried out as a one‐pot process, involves the direct formation of stable alkenyl sulfonium salt intermediates, utilises a commercially available sulfoxide, catalyst, and ligand, operates at ambient temperature, accommodates sp‐, sp2‐, and
Pd-Catalyzed Regioselective Arylboration of Vinylarenes
作者:Kai Yang、Qiuling Song
DOI:10.1021/acs.orglett.6b02527
日期:2016.11.4
A palladium-catalyzed 1,2-arylboration of vinylarenes with aryldiazonium tetrafluoroborates and bis(pinacolato)diboron has been disclosed. It is reported for the first time that styrene derivatives can be successfully employed as good substrates for 1,2-arylboration of alkenes. Mechanistic studies suggest that no Pd–H reinsertion occurred under our standard conditions, which is the key for the success
Synthesis of 1-, 2-, 3- and 4-fluorobenzo[c]phenanthrenes by photocyclization of appropriate β-naphth-l-yl fluorostyrenes is described. An improved synthesis of 6-fluorobenzo[c]phenanthrene was developed. Partial photochemical debromination occured upon cyclization of 2-bromo-7-fluorobenzo[c]phenanthrene.