Aminobromination of olefins with TsNH<sub>2</sub>and NBS as the nitrogen and bromine sources mediated by hypervalent iodine in a ball mill
作者:Xue-Liang Wu、Jing-Jing Xia、Guan-Wu Wang
DOI:10.1039/b717333d
日期:——
A series of olefins including α,β-unsaturated ketones, cinnamates, cinnamides and styrenes have been aminobrominated with good yields and excellent diastereoselectivities under mechanical milling conditions, using TsNH2 and NBS as the nitrogen and bromine sources, promoted by (diacetoxyiodo)benzene.
The carbon dioxide (CO2)-induced amidobromination of olefins with bromamine-T is described. The method can be used in reactions with a wide range of olefins, both aromatic and aliphatic, as well as electron-rich and deficient olefins, leading to the regioselective formation of amidobrominated compounds.
proceeds rapidly under mild conditions with high regioselectivity. Olefins react with TsNBr2 in moist THF to form δ-amino ether at roomtemperature. Treatment of TsNBr2 with olefin in MeCN at roomtemperature produced imidazoline in high yield. Further modification of the reaction condition resulted in the development of a one-step procedure for the synthesis of N-acetyl,N′-tosyl diamine derivatives directly
已经发现N,N-二溴-对甲苯磺酰胺(TsNBr 2)是用于各种氨基官能化反应的有效试剂。该试剂既可作为亲电子溴源,也可作为胺在不同条件下与烯烃反应,从而产生氨基醚,咪唑啉,二胺和氨基溴。该反应在温和条件下以高区域选择性快速进行。烯烃与TsNBr 2在潮湿的THF中反应,在室温下形成δ-氨基醚。在室温下,在MeCN中用烯烃处理TsNBr 2可以高产率生产咪唑啉。反应条件的进一步改变导致了一步合成步骤的发展。N-乙酰基,N'-甲苯磺酰基二胺衍生物直接来自烯烃。当烯烃与2.4摩尔当量TsNBr的处理2中K的存在2 CO 3,Ñ,Ñ在适中的产率获得'-ditosyl二胺衍生物。当在室温下在干燥的CH 2 Cl 2中用试剂处理烯烃时,观察到氨基溴的瞬时形成。