Radical substitution with azide: TMSN<sub>3</sub>–PhI(OAc)<sub>2</sub>as a substitute of IN<sub>3</sub>
作者:Christian Marcus Pedersen、Lavinia Georgeta Marinescu、Mikael Bols
DOI:10.1039/b500037h
日期:——
TMSN3 and PhI(OAc)2 were found to promote high-yield azide substitution of ethers, aldehydes and benzal acetals. The reaction is fast and occurs at zero to ambient temperature in acetonitrile. However, it is essential for the reaction that TMSN3 is added subsequent to the mixture of PhI(OAc)2 and the substrate. A primary deuterium kinetic isotope effect was found for the azidonation of benzyl ethers
(DPPA). The reactionprocedure is quite simple, occurring by refluxing an equimolecular mixture of a carboxylic acid, DPPA, and triethylamine in the presence of a hydroxyl component. Aromatic, aliphatic, and heterocyclic carboxylic acids underwent rearrangements in satisfactory yields. As this modified Curtins reaction is much simpler and less laborious than the classical Curtius reaction and proceeds
作者:Lavinia Marinescu、Jacob Thinggaard、Ib B. Thomsen、Mikael Bols
DOI:10.1021/jo035163v
日期:2003.11.1
Aliphatic and aromatic aldehydes can be converted to acyl azides by treatment with iodine azide at 0-25 degrees C. If the reaction is performed at reflux Curtiusrearrangement occurs and carbamoylazides are obtained in 70-97% yield from the aldehyde. The reaction was shown to have a radical mechanism.
Iodobenzene Dichloride in Combination with Sodium Azide for the Effective Synthesis of Carbamoyl Azides from Aldehydes
作者:Chi Zhang、Xiao-Qiang Li、Xue-Fei Zhao
DOI:10.1055/s-2008-1067196
日期:2008.8
Various aliphatic and aromatic aldehydes are converted into their corresponding carbamoyl azides in good to excellent yields with the use of a combined reagent system of iodobenzenedichloride and sodium azide in acetonitrile under nitrogen.
A novel method was developed for the synthesis of carbamoyl azides from hydroxamic acids via the Lossen rearrangement using diphenyl phosphorazidate, which acts as both the activator and azide source to produce the azidesvia an isocyanate intermediate. Using this method, various hydroxamic acids were converted into the corresponding carbamoyl azides, enabling their preparation without the use of highly