Sterically Hindered Chelating Alkyl Phosphines Provide Large Rate Accelerations in Palladium-Catalyzed Amination of Aryl Iodides, Bromides, and Chlorides, and the First Amination of Aryl Tosylates

Cross-coupling between substrates that can be easily derived from phenols is highly attractive due to the abundance and low cost of phenols. Here, we report a dual nickel/palladium-catalyzed reductive cross-coupling between aryl tosylates and aryl triflates; both substrates can be accessed in just one step from readily available phenols. The reaction has a broad functional group tolerance and substrate scope (>60 examples). Furthermore, it displays low sensitivity to steric effects demonstrated by the synthesis of a 2,2’disubstituted biaryl and a fully substituted aryl product. The widespread presence of phenols in natural products and pharmaceuticals allow for straightforward late-stage functionalization, illustrated with examples such as Ezetimibe and tyrosine. NMR spectroscopy and DFT calculations indicate that the nickel catalyst is responsible for activating the aryl triflate, while the palladium catalyst preferentially reacts with the aryl tosylate.

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Palladium-Catalyzed Asymmetric Annulation Between Aryl Iodides and Racemic Epoxides Using a Chiral Norbornene Cocatalyst

10.26434/chemrxiv.6635312 ◽

2018 ◽

Author(s):

Guangbin Dong ◽

Renhe Li

Keyword(s):

Isopropyl Ester ◽

Synthetic Route ◽

Initial Development ◽

Aryl Iodides ◽

Palladium Catalyzed

Herein, we describe our initial development of an asymmetric Pd-catalyzed annulation between aryl iodides and racemic epoxides for synthesis of 2,3-dihydrobenzofurans using a chiral norbornene cocatalyst. A series of enantiopure ester-, amide- and imide-substituted norbornenes have been prepared with a reliable synthetic route. Promising enantioselectivity (42-45% ee) has been observed using the isopropyl ester-substituted norbornene (N1*) and the amide-substituted norbornene (N7*).

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Palladium-Catalyzed One-Pot Three- or Four-Component Coupling of Aryl Iodides, Alkynes, and Amines through CN Bond Cleavage: Efficient Synthesis of Indole Derivatives

Chemistry - A European Journal ◽

10.1002/chem.201304215 ◽

2014 ◽

Vol 20 (9) ◽

pp. 2605-2612 ◽

Cited By ~ 37

Author(s):

Wei Hao ◽

Weizhi Geng ◽

Wen-Xiong Zhang ◽

Zhenfeng Xi

Keyword(s):

Bond Cleavage ◽

Indole Derivatives ◽

Efficient Synthesis ◽

One Pot ◽

Aryl Iodides ◽

Palladium Catalyzed

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Selective Synthesis of N-Acylnortropane Derivatives in Palladium-Catalysed Aminocarbonylation

Molecules ◽

10.3390/molecules26061813 ◽

2021 ◽

Vol 26 (6) ◽

pp. 1813

Author(s):

László Kollár ◽

Ádám Erdélyi ◽

Haroon Rasheed ◽

Attila Takács

Keyword(s):

Synthetic Method ◽

Selective Synthesis ◽

Varied Structure ◽

Biological Importance ◽

Aryl Iodides ◽

Palladium Catalyzed ◽

Derivatives Of

The aminocarbonylation of various alkenyl and (hetero)aryl iodides was carried out using tropane-based amines of biological importance, such as 8-azabicyclo[3.2.1]octan-3-one (nortropinone) and 3α-hydroxy-8-azabicyclo[3.2.1]octane (nortropine) as N-nucleophile. Using iodoalkenes, the two nucleophiles were selectively converted to the corresponding amide in the presence of Pd(OAc)2/2 PPh3 catalysts. In the presence of several iodo(hetero)arenes, the application of the bidentate Xantphos was necessary to produce the target compounds selectively. The new carboxamides of varied structure, formed in palladium-catalyzed aminocarbonylation reactions, were isolated and fully characterized. In this way, a novel synthetic method has been developed for the producing of N-acylnortropane derivatives of biological importance.

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