Synthesis of Benzoxazolones from Nitroarenes or Aryl Halides
摘要:
A simple and effective method for the preparation of benzoxazolones from nitroarenes or aryl halides is described. Partial reduction of a nitro group in the presence of a chloroformate followed by a microwave-assisted rearrangement/ring closure sequence provides a convenient and practical procedure to prepare this important pharmacophore. Rearrangement precursors were also accessed from aryl halides through transition-metal-catalyzed coupling.
[EN] METHODS FOR PREPARING BENZOXAZINES<br/>[FR] PROCÉDÉS DE PRÉPARATION DE BENZOXAZINES
申请人:BP OIL INT
公开号:WO2020260418A1
公开(公告)日:2020-12-30
A method is provided for preparing a compound ƒ. The method comprises carrying out the following reaction: (i), (ii), (iii) where: PG represents a protecting group, LG represents a leaving group, and L and L' are independently selected from OH and leaving groups, or L and L' together form a group selected from -O-C(O)-O- and -O-.
An efficient 1-pot procedure for the Zn-mediated redn. of nitro arenes in the presence of chloroformates leading to the corresponding N,O-bisprotected hydroxylamine is described. Reactions proceed smoothly under ambient conditions in THF-water mixts. in good to excellent yield (34-81%). Solvolysis of the bisprotected hydroxylamines with NaOMe at room temp. provides access to synthetically versatile
Synthesis of Benzoxazolones from Nitroarenes or Aryl Halides
作者:Achim Porzelle、Michael D. Woodrow、Nicholas C. O. Tomkinson
DOI:10.1021/ol902885j
日期:2010.2.19
A simple and effective method for the preparation of benzoxazolones from nitroarenes or aryl halides is described. Partial reduction of a nitro group in the presence of a chloroformate followed by a microwave-assisted rearrangement/ring closure sequence provides a convenient and practical procedure to prepare this important pharmacophore. Rearrangement precursors were also accessed from aryl halides through transition-metal-catalyzed coupling.