has also been observed. Thus, photolysis of fluorenone oxime tert-butyl oxalate results in the formation of tert-butoxycarbonyl radicals, which subsequently decay, mainly yielding CO2 and tert-butyl radicals. The benzyloxycarbonyl radical and the acetoneiminoxycarbonyl radical both decarboxylate too rapidly to be detected with our spectrometer (25 ns rise-time). Upon purging the solution with oxygen
Preparation of β- and γ-lactams from carbamoyl radicals derived from oxime oxalate amides
作者:Eoin M. Scanlan、Alexandra M. Z. Slawin、John C. Walton
DOI:10.1039/b315223e
日期:——
synthetic route to oxime oxalate amides was developed and applied to the preparation of molecules incorporating N-benzyl-N-alkenyl amides linked with acetone oxime or benzaldoxime units. In addition, 2-substituted-thiazolidine-4-carboxylic acid methyl esteramides of oxalyl benzaldoxime were also prepared. It was shown by EPR spectroscopy that the oxalyl benzaldoxime amides dissociated to produce benziminyl
Preparation and Beckmann Rearrangement of<i>O</i>-(Chlorooxalyl)oximes
作者:Johannes C. Jochims、Sabine Hehl、Siegfried Herzberger
DOI:10.1055/s-1990-27112
日期:——
Oximes 1 react with phosgene or oxalyl chloride to give O-(chloroformyl)- 2, or O-(chlorooxalyl) oximes 8, which undergo Beckmann rearrangement with antimony pentachloride to afford nitrilium hexachloroantimonates 3 in high yields. With di- or triphosgene (4 or 6) oximes 1 form mixtures of O-(chloroformyl)- 2 and O-(trichloromethoxyformyl)oximes 5. The O-(chlorooxalyl)oximes 8 further characterized as esters 10 and amides 11. With N,N-dimethylformamide the nitrilium salts 3 react to give N-acyl formamidinium salts 12.