Fluorinated Diazo Diketones in Rhodium(II)-Catalyzed Reactions with Sultams: Chemoselective O-Functionalization of Amide Carbonyl Groups

✍ Scribed by Valeria M. Zakharova; Bärbel Schulze; Ludmila L. Rodina; Joachim Sieler; Valerij A. Nikolaev

• Publisher: John Wiley and Sons
• Year: 2005
• Tongue: German
• Weight: 321 KB
• Volume: 88
• Category: Article
• ISSN: 0018-019X
• DOI: 10.1002/hlca.200590146

✦ Synopsis

Abstract

Rhodium(II)‐catalyzed decomposition of fluorinated diazo diketones in the presence of isothiazole‐3(2__H__)‐one 1,1‐dioxides offers a chemoselective and useful tool for O‐functionalization of their CO groups by interaction with transient fluorine‐containing Rh^II^‐diketocarbenoids. The resulting O‐alkylimidates of isothiazole 1,1‐dioxides, bearing (trifluoromethyl)acetyl groups, easily react with traces of H~2~O giving rise to stable hydrates of the perfluoroacetyl groups. No O→N isomerization of O‐alkylimidates (similar to the Lander–Chapman rearrangement) was observed under the reaction conditions studied.