Electrophilic Bromination ofN-Acylated Cyclohex-3-en-1-amines: Synthesis of 7-Azanorbornanes
作者:Peter Kapferer、Andrea Vasella
DOI:10.1002/hlca.200490249
日期:2004.11
dibromides 27, 29, and 32 into the 7-azanorbornanes 42, 49, and 53. The diols 45 and 57 were obtained from 42 and 53via HBr elimination and stereoselective dihydroxylation; they proved weak inhibitors of several glycosidases. In no case could the formation of a bicyclic azetidine (6-azabicyclo[3.1.1]heptane) from the dibromides 26 and 30 be observed.
分子内溴酰胺化和的二溴化-环化Ñ -acylcyclohex -3-烯-1-胺4,8,9,11,13,14,和16中认为是双环胺的合成进行了研究作为构建基块和潜在的糖苷酶抑制剂的兴趣。的trifluoroacetamides 4,9,和14与反应Ñ在AcOH溴代琥珀酰亚胺(NBS),得到良好的产率二氢-1,3-恶嗪。烯烃8和9的二溴化的立体选择性取决于保护基的性质,试剂和反应条件。Br 2 in CH 2 Cl 2将烯烃8和9主要转化为双轴反式,即反式-二溴化物。的溴化9与PhMe中3 NBR 3或被Br 2的Et的存在下4 NBR主要得到diequatorial反式,顺式- 27除了一些反式,反式- 28。所述的类似溴化C(5) -取代Ñ酰基-4- aminocyclohexenes 11,13,14,和16与的PhMe 3NBr 3伴随着分子内副反应,该副反应被添加过量的Et 4 NB