Microwave-assisted benzyl mono- and dibromination in diethyl carbonate as environmentally friendly alternative to radical bromination in carbon tetrachloride
作者:Subramanya R. K. Pingali、Sunil K. Upadhyay、Branko S Jursic
DOI:10.1039/c0gc00794c
日期:——
environmentally friendly benzyl mono- and di-bromination synthetic procedure was developed that is superior to the classic carbon tetrachloride bromination procedure in both reaction time and isolated yield. This new reaction was performed in diethyl carbonate as reaction media using microwave instead of conventional heating. Both the solvent and the brominating reagent N-bromosuccinimide (prepared from succinimide
A Simple Key for Benzylic Mono- and <b><i>gem</i></b>-Dibromination of Primary Aromatic Amine Derivatives Using Molecular Bromine
作者:Narshinha Argade、Anirban Kar
DOI:10.1055/s-2002-19812
日期:——
Quantitative benzylic mono- and gem-dibromination on primary aromatic amine derivatives have been achieved using molecular bromine and by protecting the amino group as a succinimide moiety. The reactions of N-(o/m/p-tolyl)succinimides 5a-c with 1.25 equivalents of molecular bromine in CCl4 at room temperature furnished the corresponding benzylic monobrominated products 6a-c in 92-94% yields, while with 2.5 equivalents of molecular bromine in refluxing CCl4 gem-dibromo products 7a-c were obtained in 94-96% yields. It is also possible to carry out nuclear bromination in these N-protected primary aromatic amines at an alternate site by using suitably substituted aniline derivatives. Thus the reaction of 3 with 1.25 equivalents of molecular bromine in acetic acid gave the desired monobrominated product 4 in nearly 100% yield.
The reactivity of imide carbonyl groups in the intramolecular aza-Wittig reaction. An efficient route to iminolactam derivatives
作者:Shoji Eguchi、Hisato Takeuchi
DOI:10.1039/c39890000602
日期:——
Treatment of N-(ω-azidoalkyl)imides with triphenylphosphine in toluene or xylene under reflux gave the corresponding iminolactam derivatives in good yields via the Staudinger reaction followed by the intramolecular aza-Wittig reaction.