scholarly journals Regiocontroled Pd-catalysed C5-arylation of 3-substituted thiophene derivatives using a bromo-substituent as blocking group

2016 ◽  
Vol 12 ◽  
pp. 2197-2203 ◽  
Author(s):  
Mariem Brahim ◽  
Hamed Ben Ammar ◽  
Jean-François Soulé ◽  
Henri Doucet
Keyword(s):  
Suzuki Coupling ◽  
Pd Catalyst ◽  
Direct Arylation ◽  
Blocking Group ◽  
Aryl Bromides ◽  
Thiophene Derivatives ◽  
High Yields

The use of a bromo-substituent as blocking group at the C2-position of 3-substituted thiophenes allows the regioselective introduction of aryl substituents at C5-position via Pd-catalysed direct arylation. With 1 mol % of a phosphine-free Pd catalyst, KOAc as the base and DMA as the solvent and various electron-deficient aryl bromides as aryl sources, C5-(hetero)arylated thiophenes were synthesized in moderate to high yields, without cleavage of the thienyl C–Br bond. Moreover, sequential direct thienyl C5-arylation followed by Pd-catalysed direct arylation or Suzuki coupling at the C2-position allows to prepare 2,5-di(hetero)arylated thiophenes bearing two different (hetero)aryl units in only two steps. This method provides a “green” access to arylated thiophene derivatives as it reduces the number of steps to prepare these compounds and also the formation of wastes.

scholarly journals Efficient synthesis of π-conjugated molecules incorporating fluorinated phenylene units through palladium-catalyzed iterative C(sp2)–H bond arylations

2015 ◽  
Vol 11 ◽  
pp. 2012-2020 ◽  
Author(s):  
Fatiha Abdelmalek ◽  
Fazia Derridj ◽  
Safia Djebbar ◽  
Jean-François Soulé ◽  
Henri Doucet
Keyword(s):  
Conjugated Oligomers ◽  
Efficient Synthesis ◽  
Conjugated Molecules ◽  
Direct Arylation ◽  
Heteroaromatic Compounds ◽  
Aryl Bromides ◽  
Palladium Catalyzed ◽  
High Yields

We report herein a two or three step synthesis of fluorinated π-conjugated oligomers through iterative C–H bond arylations. Palladium-catalyzed desulfitative arylation of heteroarenes allowed in a first step the synthesis of fluoroaryl-heteroarene units in high yields. Then, the next steps involve direct arylation with aryl bromides catalyzed by PdCl(C3H5)(dppb) to afford triad or tetrad heteroaromatic compounds via regioselective activation of C(sp2)–H bonds.

C−H Arylation of Thiophenes with Aryl Bromides by a Parts-per-Million Loading of a Palladium NNC-Pincer Complex

Synlett ◽  
2020 ◽  
Vol 31 (16) ◽  
pp. 1634-1638
Author(s):  
Yasuhiro Uozumi ◽  
Anggi Eka Purta ◽  
Shun Ichii ◽  
Aya Tazawa
Keyword(s):  
Pivalic Acid ◽  
Efficient Synthesis ◽  
Direct Arylation ◽  
Pincer Complex ◽  
Aryl Bromides ◽  
Thiophene Derivatives

A palladium NNC-pincer complex efficiently catalyzed the direct arylation of thiophene derivatives with extremely low palladium loadings of the order of parts per million. Thus, the reaction of various thiophenes with aryl bromides in the presence of 25–100 mol ppm of chlorido[(2-phenyl-κ-C 2)-9-phenyl-1,10-phenanthroline-κ2-N,N′]palladium(II) NNC-pincer complex, K2CO3, and pivalic acid in N,N-dimethyl­acetamide afforded the corresponding 2- or 5-arylated thiophenes in good to excellent yields. A combination of the present C–H arylation and Hiyama coupling with the same NNC-pincer complex provides an efficient synthesis of unsymmetrical 2,5-thiophenes with catalyst loadings at mol ppm levels.

scholarly journals Hindered aryl bromides for regioselective palladium-catalysed direct arylation at less favourable C5-carbon of 3-substituted thiophenes

2014 ◽  
Vol 10 ◽  
pp. 1239-1245 ◽  
Author(s):  
Rongwei Jin ◽  
Charles Beromeo Bheeter ◽  
Henri Doucet
Keyword(s):  
Palladium Catalyst ◽  
Thiophene Ring ◽  
Aryl Bromide ◽  
Direct Arylation ◽  
Bond Functionalization ◽  
Aryl Bromides ◽  
Thiophene Derivatives ◽  
Coupling Partner

The use of the congested aryl bromide 2-bromo-1,3-dichlorobenzene as coupling partner allows to modify the regioselectivity of the arylation of 3-substituted thiophene derivatives in favour of carbon C5. The coupling of this aryl bromide with a variety of 3-substituted thiophenes gave in all cases the desired 5-arylation products in moderate to good yields using only 0.5 mol % of a phosphine-free and air-stable palladium catalyst. Then, from these 5-arylthiophenes, a second palladium-catalysed C–H bond functionalization at C2 of the thiophene ring allows the synthesis of 2,5-diarylthiophenes with two different aryl units.

Direct Arylation of Heteroaromatic Compounds with Congested, Functionalised Aryl Bromides at Low Palladium/Triphosphane Catalyst Loading

2011 ◽  
Vol 17 (23) ◽  
pp. 6453-6461 ◽  
Author(s):  
David Roy ◽  
Sophal Mom ◽  
Dominique Lucas ◽  
Hélène Cattey ◽  
Jean‐Cyrille Hierso ◽  
...  
Keyword(s):  
Catalyst Loading ◽  
Direct Arylation ◽  
Heteroaromatic Compounds ◽  
Aryl Bromides

Direct Arylation of Imidazo[1,2-b]pyridazines: Microwave-Assisted One-Pot Suzuki Coupling/Pd-Catalysed Arylation

2010 ◽  
Vol 2010 (5) ◽  
pp. 862-871 ◽  
Author(s):  
Ahmed El Akkaoui ◽  
Sabine Berteina-Raboin ◽  
Abderrahim Mouaddib ◽  
Gérald Guillaumet
Keyword(s):  
Suzuki Coupling ◽  
One Pot ◽  
Direct Arylation ◽  
Microwave Assisted

Highly electron-poor Buchwald-type ligand: application for Pd-catalysed direct arylation of thiophene derivatives and theoretical consideration of the secondary Pd0–arene interaction

2015 ◽  
Vol 44 (45) ◽  
pp. 19642-19650 ◽  
Author(s):  
Toshinobu Korenaga ◽  
Ryo Sasaki ◽  
Kazuaki Shimada
Keyword(s):  
Theoretical Consideration ◽  
Direct Arylation ◽  
Thiophene Derivatives

Highly electron-poor SPhos ligands stabilised the Pd complex by secondary Pd0–arene interaction.

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