A diene-transmissive Diels–Alder reaction involving inverse electron-demand hetero-Diels–Alder cycloaddition of cross-conjugated azatrienes
作者:Satoru Kobayashi、Tomoki Furuya、Takashi Otani、Takao Saito
DOI:10.1016/j.tetlet.2008.05.054
日期:2008.7
electron-demand hetero-Diels–Alder reaction of N-sulfonyldivinylmethanimine with electron-rich dienophiles (ethyl vinyl ether and ethyl vinyl sulfide) affords [4+2] cycloadducts with high endo selectivity. The monocycloadducts then undergo a second Diels–Alder reaction on the newly formed diene unit with electron-deficient dienophiles (tetracyanoethylene, 4-phenyl-1,2,4-triazoline-3,5-dione, and N-phenylmaleimide)
N-磺酰基二乙烯基甲亚胺与富电子的亲二烯体(乙基乙烯基醚和乙基乙烯基硫化物)的初始电子反杂Diels-Alder逆反应提供了具有高内选择性的[4 + 2]环加合物。然后,单环加合物在新形成的二烯单元上与缺电子的亲二烯体(四氰基乙烯,4-苯基-1,2,4-三唑啉-3,5-二酮和N-苯基马来酰亚胺)进行第二次狄尔斯-阿尔德反应,得到高立体选择性地交叉的双环加合物,六氢和八氢喹啉和八氢吡啶并哒嗪。