Photochemical Protection of Amines with Cbz and Fmoc Groups
作者:Céline Helgen、Christian G. Bochet
DOI:10.1021/jo026581n
日期:2003.3.1
The photochemical conversion of amines into carbamates was achieved using N-Cbz- N-Fmoc-, and N-Boc-5,7-dinitroindolines. This reaction allows the protection of amines in neutral medium. Primary and unhindered secondary amines were protected to yield their benzyloxycarbonyl- and 9-fluorenylmethoxycarbonyl derivatives efficiently, whereas bulky amines or anilines gave low yields or no product. On the other hand, the formation of N-Boc compounds, although possible, proceeded only with low yields.
A Straightforward Entry to γ-Trifluoromethylated Allenamides and Their Synthetic Applications
allenamides were obtained in good to excellent yields through a base-induced isomerization from the corresponding protected trifluoromethylated propargylic amines. This method, which simply required the treatment of the starting propargylic amines with sodium hydroxide in THF, was found to be fairly general and tolerates various alkyl and aryl substituents and a range of protecting groups on the nitrogen