Synthesis of Halogenated Phenols by Directed <i>ortho</i>-Lithiation and <i>ipso</i>-Iododesilylation Reactions of <i>O</i>-Aryl <i>N</i>-Isopropylcarbamates
作者:Dieter Hoppe、Matthias Kauch
DOI:10.1055/s-2006-926462
日期:2006.5
The regioselective synthesis of halogenated phenols via directed ortho-lithiation reactions of in situ N-silylated O-aryl N-isopropylcarbamates is reported. This protocol is complemented by ipso-iododesilylation reactions of C-silylated carbamates and iodine-magnesium exchange reactions, which are facilitated by the adjacent carbamoyl group. These methods provide an entry into a series of o-fluoro-
A versatile synthesis of 1,4-benzodiazepine derivatives through the reaction of various 3-(trifluoromethanesulfonyloxy)benzynes with N-(p-toluenesulfonyl)imidazolidin-2-ones is reported. This reaction system provides a 1,4-benzodiazepine bearing a trifluoromethanesulfonyloxy group as a single regioisomer among the four possible regioisomers.