Download PDF
Synthesis 1988; 1988(3): 246-248
DOI: 10.1055/s-1988-27532
communication
© Georg Thieme Verlag, Rüdigerstr. 14, 70469 Stuttgart, Germany. All rights reserved. This journal, including all individual contributions and illustrations published therein, is legally protected by copyright for the duration of the copyright period. Any use, exploitation or commercialization outside the narrow limits set by copyright legislation, without the publisher's consent, is illegal and liable to criminal prosecution. This applies in particular to photostat reproduction, copying, cyclostyling, mimeographing or duplication of any kind, translating, preparation of microfilms, and electronic data processing and storage.

A Simple, One-Step Synthesis of 3,4-Dihydro-4-phenacyl-2H-1,3-benzoxazin-2-ones

Nazih Latif* , Fahmy M. Asaad, Nabil Grant
  • *National Research Centre, Dokki, Cairo, A. R. Egypt
Further Information

Publication History

Publication Date:
20 August 2002 (online)

  PDF Download  Permissions and Reprints All articles of this category

2-Hydroxychalcones 1a, b react readily with alkyl and aryl isocyanates in the presence of potassium hydroxide to give directly the corresponding 3-alkyl- and 3-aryl-3,4-dihydro-4-phenacyl-2H-1,3-benzoxazin-2-ones 3. The 2-thione analogues 5a, b are similarly obtained by reacting 1a, b with methyl isothiocyanate. Thiones 5 are readily oxidized by yellow mercuric oxide to the corresponding oxo compounds 3. The direct formation of benzoxazinones from chalcones apparently proceeds through the intermediate formation of open chain carbamates.The latter are cleaved readily by p-toluenesulfonyl chloride under base catalysis to give the corresponding sulfonates.