3878-46-4Relevant articles and documents
Remarkably Efficient Iridium Catalysts for Directed C(sp2)-H and C(sp3)-H Borylation of Diverse Classes of Substrates
Chattopadhyay, Buddhadeb,Hassan, Mirja Md Mahamudul,Hoque, Md Emdadul
supporting information, p. 5022 - 5037 (2021/05/04)
Here we describe the discovery of a new class of C-H borylation catalysts and their use for regioselective C-H borylation of aromatic, heteroaromatic, and aliphatic systems. The new catalysts have Ir-C(thienyl) or Ir-C(furyl) anionic ligands instead of the diamine-type neutral chelating ligands used in the standard C-H borylation conditions. It is reported that the employment of these newly discovered catalysts show excellent reactivity and ortho-selectivity for diverse classes of aromatic substrates with high isolated yields. Moreover, the catalysts proved to be efficient for a wide number of aliphatic substrates for selective C(sp3)-H bond borylations. Heterocyclic molecules are selectively borylated using the inherently elevated reactivity of the C-H bonds. A number of late-stage C-H functionalization have been described using the same catalysts. Furthermore, we show that one of the catalysts could be used even in open air for the C(sp2)-H and C(sp3)-H borylations enabling the method more general. Preliminary mechanistic studies suggest that the active catalytic intermediate is the Ir(bis)boryl complex, and the attached ligand acts as bidentate ligand. Collectively, this study underlines the discovery of new class of C-H borylation catalysts that should find wide application in the context of C-H functionalization chemistry.
Synthesis of 2-arylquinazolin-4(3H)-ones by N-aryl benzamidines with aromatic carbonates
Aikawa, Shunichi,Sekiguchi, Chiharu,Yamazaki, Yuko,Hattori, Mika,Isaka, Tatsuya,Yoshida, Yasuhiko,Ihara, Shogo
, p. 343 - 348 (2014/04/17)
The reaction of N-aryl benzamidines 1a, 1b, 1c, 1d, 1e, 1f, 1g, 1h, 1i, 1j, 1k, 1l, 1m, 1n with diphenyl carbonate 2a or ethyl phenyl carbonate 2b synthesized 2-arylquinazolin-4(3H)-ones 3a, 3b, 3c, 3d, 3e, 3f, 3g, 3h, 3i, 3j, 3k, 3l, 3m, 3n in simple and
PROCESS FOR CONTINUOUS PRODUCTION OF ORGANIC CARBONATES OR ORGANIC CARBAMATES AND SOLID CATALYSTS THEREFORE
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Page/Page column 25, (2009/08/18)
Processes for the alcoholysis, inclusive of transesterification and/or disproportionation, of reactants are disclosed. The alcoholysis process may include feeding reactants and a trace amount of soluble organometallic compound to a reactor comprising a solid alcoholysis catalyst, wherein the soluble organometallic compound and the solid alcoholysis catalyst each independently comprise a Group II to Group VI element, which may be the same element in various embodiments. As an example, diphenyl carbonate may be continuously produced by performing transesterification over a solid catalyst followed by disproportionation, where a trace amount of soluble organometallic compound is fed to the transesterification reactor. Also disclosed is a process for reactivating a spent solid alcoholysis catalyst, such as a catalyst useful for transesterifications and/or disproportionations, the process including removing polymeric materials deposited on the catalyst and re-depositing catalytically active metals on the solid catalyst.