Palladium(0)-catalyzed cyclopropanation of benzyl bromides via C(sp3)–H bond activation

2014 ◽  
Vol 50 (28) ◽  
pp. 3692-3694 ◽  
Author(s):  
Jiangang Mao ◽  
Shuo-Qing Zhang ◽  
Bing-Feng Shi ◽  
Weiliang Bao
Keyword(s):  
Bond Activation ◽  
Coupling Reaction ◽  
Type Coupling

A novel Pd(0)-catalyzed domino cyclopropanation reaction was established. The process involves a Heck-type coupling reaction and a C(sp3)–H activation.

ChemInform Abstract: Direct Dehydroxylative Coupling Reaction of Alcohols with Organosilanes Through Si-X Bond Activation by Halogen Bonding.

ChemInform ◽  
2015 ◽  
Vol 46 (44) ◽  
pp. no-no
Author(s):  
Masato Saito ◽  
Nobuya Tsuji ◽  
Yusuke Kobayashi ◽  
Yoshiji Takemoto
Keyword(s):  
Bond Activation ◽  
Coupling Reaction ◽  
Halogen Bonding

Synthesis and structure-property relationships of novel poly(p-xylylene)s with aromatic substituents

e-Polymers ◽  
2001 ◽  
Vol 1 (1) ◽  
Author(s):  
Michael Ishaque ◽  
Ralf Wombacher ◽  
Joachim H. Wendorff ◽  
Andreas Greiner
Keyword(s):  
Chemical Vapor ◽  
Coupling Reaction ◽  
Structure Property ◽  
Ambient Conditions ◽  
Structure Property Relationships ◽  
Aryl Bromides ◽  
Phenyl Rings ◽  
Type Coupling ◽  
Derivatives Of ◽  
Conversion Of Alcohols

AbstractTwo step synthesis of educts for the synthesis of poly(p-xylylene)s was accomplished by Grignard-type coupling reaction of 4-bromotoluene and different aldehydes or p-tolylaldehyde and different aryl bromides followed by conversion of alcohols into corresponding chlorides. Derivatives of poly(p-xylylene) (PPX) were obtained by vapor phase pyrolysis/chemical vapor deposition (CVD) or Gilch-type polymerization of these chlorides. Functional groups along the PPX main chain were introduced by substituted phenyl rings in a-position. The resulting PPXs are soluble under ambient conditions and are amorphous in the solid state. The glass transition temperatures varied only slightly with substituents on the phenyl ring in a-position. Significant enhancement by substituents was found for the thermal stability under nitrogen and a considerable decrease of the surface energies by fluorinated substituents.

The oxidative coupling between benzaldehyde derivatives and phenylacetylene catalyzed by rhodium complexes via C-H bond activation

2020 ◽  
Vol 26 (1) ◽  
pp. 20-25
Author(s):  
Xinyi Zhao ◽  
Hongge Jia ◽  
Qingji Wang ◽  
Heming Song ◽  
Yanan Tang ◽  
...  
Keyword(s):  
Amino Acid ◽  
Oxidative Coupling ◽  
Bond Activation ◽  
Coupling Reaction ◽  
Reaction Yield ◽  
Rhodium Complexes ◽  
Electronic Effects ◽  
Oxidative Coupling Reaction ◽  
Excellent Activity ◽  
Benzaldehyde Derivatives

AbstractThis paper reports the use of rhodium (Rh) catalysts for the oxidative coupling reaction between phenylacetylene and benzaldehyde derivatives via C-H bond activation. These reactions were catalyzed by Rh(l-amino acid)(cod) (the l-amino acid is l-phenylalanine, l-valine or l-proline; cod is 1,5-cyclooctadiene) to obtain chromones in 12.7–88.3% yield. These new Rh catalysts have excellent activity for the coupling reaction between phenylacetylene and different benzaldehyde derivatives. It was found that the electronic effects of the benzaldehyde derivative substituent affected the reaction yield, which is in accordance with the proposed mechanism.

Environmentally Benign Microwave-Assisted Sonogashira Preparation of Aromatic Compounds

2011 ◽  
Vol 695 ◽  
pp. 113-116 ◽  
Author(s):  
Suttikiat Puechmongkol ◽  
Boonchoat Paosawatyanyong ◽  
Worawan Bhanthumnavin
Keyword(s):  
Coupling Reaction ◽  
Environmentally Benign ◽  
Conventional Heating ◽  
Microwave Activation ◽  
Sonogashira Coupling ◽  
Terminal Alkynes ◽  
Mild Conditions ◽  
Aryl Bromides ◽  
Sonogashira Coupling Reaction ◽  
Type Coupling

An efficient Sonogashira-type coupling reaction of terminal alkynes and aryl bromides by microwave activation with short reaction time under mild conditions are presented. It is illustrated herein that the traditional Sonogashira coupling reaction can be achieved with a much more efficient yet environmentally friendly condition. In contrary to the usually required 10 mol% Pd loading and the use of conventional heating at 60 °C for 24 h in order for a reaction to proceed satisfactorily, with a 100 W microwave activation, the reaction of terminal alkynes with substituted aryl bromides can be achieved with only a 2.5 mol% Pd in 10 min. The yield was improved with microwave irradiation.

Syntheses of 4-[1-(2-deoxy-β-D-ribofuranosyl)]-derivatives of 2-substituted-5-fluoroaniline: "cytosine replacement" analogs of deoxycytidine for evaluation as anticancer and antihuman immunodeficiency virus (anti-HIV) agents

2000 ◽  
Vol 78 (8) ◽  
pp. 1081-1088
Author(s):  
Zhi-Xian Wang ◽  
Leonard I Wiebe ◽  
Erik De Clercq ◽  
Jan Balzarini ◽  
Edward E Knaus
Keyword(s):  
Anticancer Agent ◽  
Coupling Reaction ◽  
Tumor Cell Lines ◽  
Immunodeficiency Virus ◽  
Sugar Ring ◽  
Type Coupling ◽  
Anti Hiv Agents ◽  
Derivatives Of ◽  
Anti Hiv ◽  
Hiv 1

A group of 4-[1-(2-deoxy-β-D-ribofuranosyl)]-derivatives of 5-fluoroaniline possessing a variety of aryl C-2 substituents (6a R = H, 6b R = F, 6c R = Me) were synthesized. Accordingly, a Heck-type coupling reaction of the 4-iodoaniline derivatives (13a–c) with the bis(tert-butyldimethylsilyl)glycal (11) in the presence of Pd(OAc)2 and Ph3As, followed by removal of the tert-butyldimethylsilyl protection groups using n-Bu4N+F-, yielded the corresponding 4-(β-D-glycero-pentofuran-3-ulos-1-yl)aniline derivatives (14a–c) having a C-3 C=O in the sugar ring. Reduction of the C-3 C=O compounds (14a–c) using NaB(OAc)3H afforded the target 4-[1-(2-deoxy-β-D-ribofuranosyl)]-derivatives of the respective 2-substituted-5-fluoroaniline (6a–c). The deoxycytidine mimic, 3-fluoro-4-[1-(2-deoxy-β-D-ribofuranosyl)]aniline (6a), in which the cytosine ring of deoxycytidine is replaced by a 4-(3-fluoroaniline) ring system, was inactive as an anticancer agent against a variety of tumor cell lines, and as an antihuman immunodeficiency virus (HIV-1, HIV-2) agent. The failure of this unnatural deoxycytidine mimic (6a) to exhibit anticancer-antiviral activity may be due to its inability to undergo phosphorylation by host cell- and virus-induced kinases.Key words: fluoroanilines, deoxycytidine mimics, anticancer-antihuman immunodeficiency virus (HIV) evaluation.

A Ni(OAc)2·4H2O-catalysed Sonogashira-type coupling reaction of aryl iodides and terminal alkynes in the presence of CuI

2012 ◽  
Vol 36 (7) ◽  
pp. 437-440 ◽  
Author(s):  
Hailong Yang ◽  
Yan Zhu ◽  
Peng Sun ◽  
Hong Yan ◽  
Linhua Lu ◽  
...  
Keyword(s):  
Coupling Reaction ◽  
Terminal Alkynes ◽  
Aryl Iodides ◽  
Type Coupling

scholarly journals Tuning of tetrathiafulvalene properties: versatile synthesis of N-arylated monopyrrolotetrathiafulvalenes via Ullmann-type coupling reactions

2015 ◽  
Vol 11 ◽  
pp. 860-868 ◽  
Author(s):  
Vladimir A Azov ◽  
Diana Janott ◽  
Dirk Schlüter ◽  
Matthias Zeller
Keyword(s):  
Hydrogen Bonds ◽  
Electrochemical Properties ◽  
Crystal Packing ◽  
Coupling Reaction ◽  
Coupling Reactions ◽  
Electronic Nature ◽  
Weak Hydrogen Bonds ◽  
Type Coupling ◽  
Variable Substitution

An Ullmann-type coupling reaction was employed for the preparation of several N-arylated monopyrrolotetrathiafulvalenes with variable substitution patterns. Spectroscopic and electrochemical properties of the coupling products strongly depend on the electronic nature of the aromatic substituents due to their direct conjugation with the tetrathiafulvalene chromophore. The crystal packing of the arylated monopyrrolotetrathiafulvalenes is primarily defined by networks of C–H···X weak hydrogen bonds and short S···S contacts involving the tetrathiafulvalene moieties.

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