41908-23-0Relevant articles and documents
Enantioselective Synthesis of Atropisomeric Biaryls using Biaryl 2,5-Diphenylphospholanes as Ligands for Palladium-Catalysed Suzuki-Miyaura Reactions
Byrne, Liam,Munday, Rachel H.,Norrby, Per-Ola,Sk?ld, Christian,Smith, Peter D.,Turner, Andrew R.
, p. 259 - 267 (2021)
Here we describe the development of biaryl 2,5-diphenylphospholanes as a new class of C2-symmetric, monodentate ligands for asymmetric Suzuki-Miyaura (ASM) reactions. Screening of a series of exemplary phospholanes led to the identification of two ligands that were used to prepare a range of atropisomeric biaryl and heterobiaryl products with good to excellent levels of enantioselectivity (up to 97:3 e.r.) under mild conditions. DFT studies suggest that the formation of a constraining ligand pocket and coordination of one of the biaryl methoxy groups in the optimised ligands to the metal centre is crucial for restricting conformational freedom in the bond-forming step. (Figure presented.).
Visible light mediated synthesis of 6H-benzo[c]chromenes: transition-metal-free intramolecular direct C-H arylation
Budén, María E.,Heredia, Micaela D.,Puiatti, Marcelo,Rossi, Roberto A.
supporting information, p. 228 - 239 (2021/12/29)
A synthetic approach towards the 6H-benzo[c]chromene ring under visible light and transition-metal-free conditions has been developed. Benzochromenes are synthesized from the corresponding (2-halobenzyl) phenyl ethers or (2-halophenyl) benzyl ethers using
Catalytic Enantioselective Synthesis of Axially Chiral Diarylmethylidene Indanones
Kumar, Prashant,Shirke, Rajendra P.,Yadav, Sonu,Ramasastry
supporting information, p. 4909 - 4914 (2021/06/30)
We describe the first atropselective Suzuki-Miyaura cross-coupling of β-keto enol triflates to access axially chiral (Z)-diarylmethylidene indanones (DAIs). The chemical, physical, and biological properties of DAIs are unknown, despite their being structurally similar to arylidene indanones, primarily due to the lack of racemic or chiral methods. Through this work, we demonstrate a general and efficient protocol for the racemic as well as the atropselective synthesis of (Z)-DAIs. An unusual intramolecular Morita-Baylis-Hillman reaction is utilized for the Z-selective synthesis of β-keto enol triflates.
Construction of Axially Chiral Arylborons via Atroposelective Miyaura Borylation
He, Yong,Li, Wangyang,Mao, Yanfei,Song, Qiuling,Wang, Hao,Xu, Jie,Yang, Kai
supporting information, p. 10048 - 10053 (2021/07/21)
Compared with the well-developed centrally chiral boron chemistry, C-B axially chiral chemistry remains elusive and challenging. Herein we report the first atroposelective Miyaura borylation of bromoarenes with unsymmetrical diboron reagents for the direct catalytic synthesis of optically active atropisomeric arylborons. This reaction features broad substrate scope and produces axially chiral arylborons with high yields and good enantioselectivities.
Enantioselective Ni-Catalyzed Electrochemical Synthesis of Biaryl Atropisomers
Chen, Song,Chen, Yue-Gang,Gao, Pei-Sen,Liu, Dong,Ma, Hong-Xing,Mei, Tian-Sheng,Qiu, Hui,Shuai, Bin,Wang, Yun-Zhao
, p. 9872 - 9878 (2020/06/27)
A scalable enantioselective nickel-catalyzed electrochemical reductive homocoupling of aryl bromides has been developed, affording enantioenriched axially chiral biaryls in good yield under mild conditions using electricity as a reductant in an undivided cell. Common metal reductants such as Mn or Zn powder resulted in significantly lower yields in the absence of electric current under otherwise identical conditions, underscoring the enhanced reactivity provided by the combination of transition metal catalysis and electrochemistry.
Intermolecular Palladium(0)-Catalyzed Atropo-enantioselective C-H Arylation of Heteroarenes
Baudoin, Olivier,Cramer, Nicolai,Guo, Shu-Min,Nguyen, Qui-Hien,Royal, Titouan
supporting information, p. 2161 - 2167 (2020/03/03)
Atropisomeric (hetero)biaryls are motifs with increasing significance in ligands, natural products, and biologically active molecules. The straightforward construction of the stereogenic axis by efficient C-H functionalization methods is extremely rare an
SMALL MOLECULE INHIBITORS OF A PROTEIN COMPLEX
-
Paragraph 00173, (2020/12/29)
Compositions and methods for treating thrombosis, inflammation, and atherosclerosis by administration of a compound that binds to KRIT1 to inhibit binding with HEG1.
A Bulky Chiral N-Heterocyclic Carbene Palladium Catalyst Enables Highly Enantioselective Suzuki-Miyaura Cross-Coupling Reactions for the Synthesis of Biaryl Atropisomers
Shen, Di,Xu, Youjun,Shi, Shi-Liang
supporting information, p. 14938 - 14945 (2019/10/11)
Axially chiral biaryl scaffolds are essential structural units in chemistry. The asymmetric Pd-catalyzed Suzuki-Miyaura cross-coupling reaction has been widely recognized as one of the most practical methods for constructing atropisomers of biaryls. However, longstanding challenges remain in this field. For example, substrate scope is often narrow and specialized, functional groups and heterocycles can lead to reduced reactivity and selectivity, bulky ortho-substituents are usually needed, and reported methods are generally inapplicable to tetra-ortho-substituted biaryls. We have developed an unprecedented highly enantioselective N-heterocyclic carbene (NHC)-Pd catalyzed Suzuki-Miyaura cross-coupling reaction for the synthesis of atropisomeric biaryls. These reactions enable efficient coupling of aryl halides (Br, Cl) or aryl triflates with various types of aryl boron compounds (B(OH)2, Bpin, Bneo, BF3K), tolerate a remarkably broad scope of functional groups and heterocycles (>41 examples), employ low loading of catalyst (0.2-2 mol %), and proceed under mild conditions. The protocol provided general and efficient access to various atropisomeric biaryls and heterobiaryls in excellent enantioselectivities (up to 99% ee) with no need of using bulky ortho-substituted substrates and was effective for the synthesis of tetra-ortho-substituent biaryls. Moreover, the method was successfully applied to the diastereo- and enantioselective synthesis of atropisomeric ternaphthalenes. Critical to the success of the reaction is the development and application of an extremely bulky C2-symmetric chiral NHC, (R,R,R,R)-DTB-SIPE, as the ligand for palladium. To the best of our knowledge, this is the first highly enantioselective (>90% ee) example of a chiral NHC-metal-catalyzed C(sp2)-C(sp2) cross-coupling reaction.
Practical, mild and efficient electrophilic bromination of phenols by a new I(iii)-based reagent: The PIDA-AlBr3 system
Satkar, Yuvraj,Ramadoss, Velayudham,Nahide, Pradip D.,García-Medina, Ernesto,Juárez-Ornelas, Kevin A.,Alonso-Castro, Angel J.,Chávez-Rivera, Ruben,Jiménez-Halla, J. Oscar C.,Solorio-Alvarado, César R.
, p. 17806 - 17812 (2018/05/28)
A practical electrophilic bromination procedure for phenols and phenol-ethers was developed under efficient and very mild reaction conditions. A broad scope of arenes was investigated, including the benzimidazole and carbazole core as well as analgesics such as naproxen and paracetamol. The new I(iii)-based brominating reagent PhIOAcBr is operationally easy to prepare by mixing PIDA and AlBr3. Our DFT calculations suggest that this is likely the brominating active species, which is prepared in situ or isolated after centrifugation. Its stability at 4 °C after preparation was confirmed over a period of one month and no significant loss of its reactivity was observed. Additionally, the gram-scale bromination of 2-naphthol proceeds with excellent yields. Even for sterically hindered substrates, a moderately good reactivity is observed.
Control of tandem isomerizations: Flow-assisted reactions of: O -lithiated aryl benzyl ethers
Lee, Hyune-Jea,Kim, Heejin,Yoshida, Jun-Ichi,Kim, Dong-Pyo
supporting information, p. 547 - 550 (2018/01/19)
Tandem chemical changes are often difficult to control at will, because they proceed rapidly through multiple unstable reactive intermediates. It is desirable to develop a novel method for controlling such tandem changes to obtain desired products with high selectivity. Herein, we report a flow microreactor platform for controlling tandem isomerizations of o-lithiated aryl benzyl ethers based on precise residence time control.
