Rhodium-Catalyzed Pyridine <i>N</i>-Oxide Assisted Suzuki–Miyaura Coupling Reaction via C(O)–C Bond Activation

Zhong, Jing; Long, Yang; Yan, Xufei; He, Shiyu; Ye, Runyou; Xiang, Haifeng; Zhou, Xiangge

doi:10.1021/acs.orglett.9b04068

Cited by 23 publications

(12 citation statements)

References 75 publications

(26 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Solvents were dried with standard procedures and degassed with N 2 . S1 – S18 , S21 were commercial reagents without further purification, S19 , S20 , S22 – S27 were from synthesis. , NMR spectra were recorded on a Bruker AVANCE 400 or 600 spectrometer. Chemical shifts are reported in ppm and coupling constants are given in Hz.…”

Section: Methodsmentioning

confidence: 99%

“…Known compound, white solid, mp: 99–100 °C; purification by column chromatography on silica gel (CH 2 Cl 2 /MeOH = 50/1), 343 mg, 64% yield, R f = 0.54 (CH 2 Cl 2 /MeOH = 20:1). IR (in KBr): 2998, 2905, 1643, 1562, 1416, 1391, 1204, 1122, 1024, 912, 823, 764, 685, 625 cm –1 .…”

Section: Methodsmentioning

confidence: 99%

“…2-Benzoylpyridine 1-Oxide (S19). Known compound, 26 General Procedure for Synthesis of α-Chloro Ketones S22− S27. To a solution of ketone (4.3 mmol, 1.0 equiv) in CH 2 Cl 2 (80 mL) and MeOH (32 mL) was added benzyltrimethylammonium dichloroiodate (8.6 mmol, 3.0 g, 2.0 equiv), and the mixture was refluxed in an oil bath for 3 h and monitored by TLC.…”

Section: ■ Conclusionmentioning

confidence: 99%

See 2 more Smart Citations

Cinchona-Alkaloid-Derived NN Ligands and Achiral Phosphines for Iridium-Catalyzed Asymmetric Hydrogenation of Heteroaromatic and α-Chloroheteroaryl Ketones

et al. 2023

View full text Add to dashboard Cite

A concise synthesis of cinchona-alkaloid-derived NN ligands bearing alkyl substituents on chiral nitrogen atoms was described. Iridium catalysts containing new chiral NN ligands and achiral phosphines were effective for the asymmetric hydrogenation of heteroaromatic ketones, which afforded corresponding alcohols in up to 99.9% ee. The same protocol was applicable to the asymmetric hydrogenation of α-chloroheteroaryl ketones. Most importantly, the gram-scale asymmetric hydrogenation of 2-acetylthiophene and 2-acetylfuran proceeded smoothly even under 1 MPa of H 2 .Article pubs.acs.org/joc

show abstract

Section: Methodsmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

Section: ■ Conclusionmentioning

confidence: 99%

See 1 more Smart Citation

Cinchona-Alkaloid-Derived NN Ligands and Achiral Phosphines for Iridium-Catalyzed Asymmetric Hydrogenation of Heteroaromatic and α-Chloroheteroaryl Ketones

et al. 2023

View full text Add to dashboard Cite

show abstract

“…80 In addition, Zhou and coworkers reported a rhodium(I)-catalyzed SMC reaction between 2-benzoyl pyridine N-oxides and arylboronic acids. 81 The N-oxide moiety acts as a DG to assist the C(aryl)−C(carbonyl) bond activation (72), and can be removed via simple treatment with PBr 3 (FIG 8Bb). This method could be applied in the synthesis of an antitumor agent 73.…”

Section: Dgs Removed Via Post-chemical Transformationsmentioning

confidence: 99%

“…Detailed mechanistic studies revealed that the reaction starts with forming hydrazone 79 from the ketone and DG-4, which then undergoes a [3+2] cycloaddition 93 with 1,3 diene followed by double bond migration to generate a pre-aromatic intermediate 80. A chelation-assisted N-H bond oxidative addition (81) followed by an aromatization-promoted C-C bond cleavage generates an alkyl-iridium or alkyl radical species, in which the latter can be converted to the former via radical recombination. Finally, C-H bond reductive elimination produced the deacetylation product 77 and release pyrazole 78 that contains the DG.…”

Section: Dgs Removed In the Catalytic Cyclementioning

confidence: 99%

Temporary or removable directing groups enable activation of unstrained C–C bonds

2020

View full text Add to dashboard Cite

Carbon−carbon (C-C) bonds constitute basic skeletons in most organic molecules. One can imagine that selective manipulation of C-C bonds would provide a direct approach to edit or alter molecular scaffolds but has been an ongoing challenge. Due to the kinetic inertness of C-C bonds, the common strategies of activating these bonds by transition metals rely on either the use of highly strained substrates or the assistance of a permanent directing group (DG), in which strain relief or formation of stable metallocycles becomes the driving force. To allow more common and less strained compounds utilized as substrates for C-C activation, the use of temporary and removable DGs has emerged as an attractive strategy in the past two decades. A variety of C−C bonds in unstrained or less strained organic molecules now can be converted to more reactive metal-carbon bonds, and further downstream transformations have led to diverse synthetic methods. This review highlights the development of catalytic approaches that can activate unstrained C-C bonds enabled by temporary or removable DGs. The content is mainly divided based on the nature of the DGs: temporary and removable. Applications of these methods in syntheses of natural products or bioactive molecules are also discussed.

show abstract

Directing Group‐Free Formal Suzuki–Miyaura Coupling of Simple Ketones Enabled by Activation of Unstrained C−C Bonds

2022

Self Cite

View full text Add to dashboard Cite

The use of ketones as electrophiles to couple with arylboronic acid derivatives via CÀ C bond activation has become a significant progress in the area of Suzuki-Miyaura coupling (SMC) reaction, in which a permanent or temporary directing group is often required to promote the activation of the unstrained CÀ C bond via oxidative addition. Herein, we disclosed the first example of directing group free formal SMC reaction of simple ketones with arylboronates via Rhcatalyzed unstrained CÀ C bond activation. A wide range of simple ketones, including aryl alkyl ketones, diaryl ketones and aryl perfluoroalkyl ketones, can serve as electrophiles to participate in the SMC reaction with aryl or perfluoroalkyl as the leaving group. The key to the success of this reaction is by means of nucleophilic addition/β-carbon elimination sequence that can activate the unstrained ketone carbonyl CÀ C bond without the assistance of directing group.

show abstract

Rhodium-Catalyzed Pyridine N-Oxide Assisted Suzuki–Miyaura Coupling Reaction via C(O)–C Bond Activation

Cited by 23 publications

References 75 publications

Cinchona-Alkaloid-Derived NN Ligands and Achiral Phosphines for Iridium-Catalyzed Asymmetric Hydrogenation of Heteroaromatic and α-Chloroheteroaryl Ketones

Cinchona-Alkaloid-Derived NN Ligands and Achiral Phosphines for Iridium-Catalyzed Asymmetric Hydrogenation of Heteroaromatic and α-Chloroheteroaryl Ketones

Temporary or removable directing groups enable activation of unstrained C–C bonds

Directing Group‐Free Formal Suzuki–Miyaura Coupling of Simple Ketones Enabled by Activation of Unstrained C−C Bonds

Contact Info

Product

Resources

About