Electrophilic Amination of 4-Fluorophenol with Diazenes: A Complete Removal of the Fluorine Atom
摘要:
The electrophilic amination of 2-fluorophenol, 4-fluorophenol, and 2-chlorophenol was observed to occur as a result of their treatment with diazenes 1-4 under mild reaction conditions in the presence of ZrCl4. The products originating from the 2-fluorophenol or 2-chlorophenol can be considered as "normal" products of amination. On the other hand, the 2-chloro-4-amino-substituted phenols obtained from the 4-fluorophenol seem to be formed in a process that involves an ipso amination, the complete removal of the fluorine atom, and the introduction of the chlorine atom.
the canonical sets, as well as regio- and stereoisomers of the tricyclic dienes, allowed generation of several anti-trypanosomal agents defining the three-dimensional shape of the pharmacophore. The candidate tricyclic dienes were selected by primary screenings and further subjected to installation of a peroxide bridge, which generated artemisinin analogues that exhibited potent in vitro anti-trypanosomal
Asymmetric Dearomatization of β-Naphthols through an Amination Reaction Catalyzed by a Chiral Phosphoric Acid
作者:Shou-Guo Wang、Qin Yin、Chun-Xiang Zhuo、Shu-Li You
DOI:10.1002/anie.201409756
日期:2014.11.20
A highly efficient catalytic asymmetricdearomatization of naphthols by means of an electrophilic amination reaction catalyzed by chiral phosphoric acid is presented. This protocol provides a facile access to functionalized β‐naphthalenone compounds with a chiral quaternary carbon center in excellent yields and enantioselectivity (up to 99 % yield, up to 96 % ee).
The electrophilic amination of 2-fluorophenol, 4-fluorophenol, and 2-chlorophenol was observed to occur as a result of their treatment with diazenes 1-4 under mild reaction conditions in the presence of ZrCl4. The products originating from the 2-fluorophenol or 2-chlorophenol can be considered as "normal" products of amination. On the other hand, the 2-chloro-4-amino-substituted phenols obtained from the 4-fluorophenol seem to be formed in a process that involves an ipso amination, the complete removal of the fluorine atom, and the introduction of the chlorine atom.
An anti-tetraamination of a 1,3-diene unit via cascade annulations of the azulenone scaffold with dicarbonyl azo-compounds
Dense and stereo-controlled integrations of C–N bonds on the azulenone scaffold are achieved by sequential (i) ene, (ii) [6 + 2]-cycloaddition, and (iii) hetero-conjugate addition reactions leading to a topologically complex bis-bridged skeleton.