1381958-89-9Relevant articles and documents
Cleavage of C(aryl)?CH3 Bonds in the Absence of Directing Groups under Transition Metal Free Conditions
Dai, Peng-Fei,Ning, Xiao-Shan,Wang, Hua,Cui, Xian-Chao,Liu, Jie,Qu, Jian-Ping,Kang, Yan-Biao
, p. 5392 - 5395 (2019)
Organic chemists now can construct carbon–carbon σ-bonds selectively and sequentially, whereas methods for the selective cleavage of carbon–carbon σ-bonds, especially for unreactive hydrocarbons, remain limited. Activation by ring strain, directing groups, or in the presence of a carbonyl or a cyano group is usually required. In this work, by using a sequential strategy site-selective cleavage and borylation of C(aryl)?CH3 bonds has been developed under directing group free and transition metal free conditions. Methyl groups of various arenes are selectively cleaved and replaced by boryl groups. Mechanistic analysis suggests that it proceeds by a sequential intermolecular oxidation and coupling of a transient aryl radical, generated by radical decarboxylation, involving a pyridine-stabilized persistent boryl radical.
COMPOUNDS FOR THE MODULATION OF PROPROTEIN CONVERTASE SUBTILISIN/KEXIN TYPE 9 (PCSK9)
-
, (2020/12/30)
The present disclosure relates to novel compounds capable of binding to PCSK9, thereby modulating PCSK9 biological activity. Also provided are compositions comprising these compounds, methods of preparing the compounds, and methods for use of the compounds in the treatment of PCSK9-related conditions and diseases.
Development and Mechanistic Studies of Iron-Catalyzed Construction of Csp2-B Bonds via C-O Bond Activation
Geng, Shasha,Zhang, Juan,Chen, Shuo,Liu, Zhengli,Zeng, Xiaoqin,He, Yun,Feng, Zhang
, p. 5582 - 5588 (2020/07/08)
Herein we describe an iron-catalyzed borylation of alkenyl and aryl carbamates through the activation of a C-O bond. This protocol exhibits high efficiency, a broad substrate scope, and the late-stage borylation of biorelevant compounds, thus providing potential applications in medicinal chemistry. Moreover, this method enables orthogonal transformations of phenol derivatives and also offers good opportunities for the synthesis of multisubstituted arenes. Preliminary mechanistic studies suggest that a FeII/FeIII catalytic cycle via a radical pathway might be involved in the reaction.
Orthogonal Nanoparticle Catalysis with Organogermanes
Fricke, Christoph,Sherborne, Grant J.,Funes-Ardoiz, Ignacio,Senol, Erdem,Guven, Sinem,Schoenebeck, Franziska
supporting information, p. 17788 - 17795 (2019/11/13)
Although nanoparticles are widely used as catalysts, little is known about their potential ability to trigger privileged transformations as compared to homogeneous molecular or bulk heterogeneous catalysts. We herein demonstrate (and rationalize) that nanoparticles display orthogonal reactivity to molecular catalysts in the cross-coupling of aryl halides with aryl germanes. While the aryl germanes are unreactive in LnPd0/LnPdII catalysis and allow selective functionalization of established coupling partners in their presence, they display superior reactivity under Pd nanoparticle conditions, outcompeting established coupling partners (such as ArBPin and ArBMIDA) and allowing air-tolerant, base-free, and orthogonal access to valuable and challenging biaryl motifs. As opposed to the notoriously unstable polyfluoroaryl- and 2-pyridylboronic acids, the corresponding germanes are highly stable and readily coupled. Our mechanistic and computational studies provide unambiguous support of nanoparticle catalysis and suggest that owing to the electron richness of aryl germanes, they preferentially react by electrophilic aromatic substitution, and in turn are preferentially activated by the more electrophilic nanoparticles.
Cobalt-Catalyzed C-F Bond Borylation of Aryl Fluorides
Lim, Soobin,Song, Dalnim,Jeon, Seungwon,Kim, Youngsuk,Kim, Hyunseok,Lee, Sanghee,Cho, Hyungdo,Lee, Byung Chul,Kim, Sang Eun,Kim, Kimoon,Lee, Eunsung
supporting information, p. 7249 - 7252 (2018/11/23)
A mild and practical cobalt-catalyzed defluoroborylation of fluoroarenes is presented for the first time. The method permits straightforward functionalization of fluoroarenes, with high selectivity for borylation of C-F over C-H bonds, and a tolerance for aerobic conditions. Furthermore, two-step 18F-fluorination was achieved for expanding the scope of 18F-positron emission tomography probes.
Synthesis of trimethylstannyl arylboronate compounds by sandmeyer-type transformations and their applications in chemoselective cross-coupling reactions
Qiu, Di,Wang, Shuai,Tang, Shengbo,Meng, He,Jin, Liang,Mo, Fanyang,Zhang, Yan,Wang, Jianbo
, p. 1979 - 1988 (2014/04/03)
A synthetic method based on Sandmeyer-type reactions to access both tin- and boron-substituted arenes from nitroaniline derivatives is described. This transformation can be applied to the synthesis of a series of functionalized trimethylstannyl arylboronates. In addition, the chemoselective reaction of the Stille and Suzuki-Miyaura cross-coupling reactions is explored, and a series of m- and p-terphenyl derivatives have been synthesized by conducting consecutive one-pot Stille and Suzuki-Miyaura cross-coupling reactions.
