Cobalt induced CH bond activation and C8-arylation of caffeine with aryl bromides
摘要:
The 8-caffeinyl cobalt(I) complex (C8-caffeinyl)Co(PMe3)(4) (1) was obtained by reaction of caffeine with cobalt(I) complex CoMe(PMe3)(4) via C-H bond activation with the escape of methane. The reaction of I with arylbromide afforded cobalt(II) complex (C8-caffeinyl)Co(PMe3)(3)Br (2) and the C,C-coupling products 8-aryl caffeine (3 and 4), 8-phenyl caffeine and 8-(2'-pyridinayl)caffeine. The crystal structures of complexes 1 and 2 were determined by X-ray diffraction. (C) 2013 Elsevier B.V. All rights reserved.
A General, Multimetallic Cross-Ullmann Biheteroaryl Synthesis from Heteroaryl Halides and Heteroaryl Triflates
作者:Kai Kang、Nathan L. Loud、Tarah A. DiBenedetto、Daniel J. Weix
DOI:10.1021/jacs.1c10907
日期:2021.12.29
medicine and materials science, the synthesis of biheteroaryls by cross-coupling remains challenging. We describe here a new, general approach to biheteroaryls: the Ni- and Pd-catalyzed multimetallic cross-Ullmann coupling of heteroaryl halides with triflates. An array of 5-membered, 6-membered, and fused heteroaryl bromides and chlorides, as well as aryltriflates derived from heterocyclic phenols,
Phosphine-Free, Palladium-Catalyzed Arylation of Heterocycles through CH Bond Activation with Pivalic Acid as a Cocatalyst
作者:Dongbing Zhao、Weida Wang、Shuang Lian、Fei Yang、Jingbo Lan、Jingsong You
DOI:10.1002/chem.200802001
日期:2009.1.26
Ligand‐free C‐arylation: A general palladium‐catalyzed C‐arylation of N‐heterocycles with aryl bromides has been performed without the presence of phosphines, the aid of CuI, or other metal additives by using pivalic acid as a cocatalyst (see scheme).
Pd-catalyzed oxidative C–H/C–H cross-coupling of pyridines with heteroarenes
作者:Bo Liu、Yumin Huang、Jingbo Lan、Feijie Song、Jingsong You
DOI:10.1039/c3sc50348h
日期:——
We have developed for the first time a general, concise and highly selective method for the C2-heteroarylation of pyridines and related azines with a broad range of heteroarenes via a two-fold C–H activation, which streamlines the previous approaches that require the activated azine N-oxide as the coupling partner.