A novel and efficient stereo-controlled synthesis of hexahydroquinolinones via the diene-transmissive hetero-Diels–Alder reaction of cross-conjugated azatrienes with ketenes and electrophilic dienophiles
作者:Satoru Kobayashi、Tomomi Semba、Taku Takahashi、Satoko Yoshida、Kotaro Dai、Takashi Otani、Takao Saito
DOI:10.1016/j.tet.2008.10.090
日期:2009.1
factors and the electronic demand of the substituents. The second Diels–Alder reaction of the initial [4+2] cycloadducts with electron-deficient dienophiles (TCNE, N-phenylmaleimide) stereoselectively yielded hexahydroquinolinone derivatives. Similarly, a tandem intermolecular–intramolecular mode of the aza-DTHDA reactions produced tetracyclic nitrogen-containing heterocycles in a regio- and stereoselective
具有N-芳基,N-烷基或N-二甲基氨基取代基的交叉共轭的氮杂三烯(二乙烯基lim或五-1,4-二烯-3-亚胺)的二烯可透过的杂狄尔斯-阿尔德(DTHDA)反应已经进行。检查。氮杂三烯与二苯乙烯酮在室温下的初始反应产生[2 + 2]环加合物的β-内酰胺,在加热后进行[1,3]-σ重排,生成正式的[4 + 2]环加合物。的反应Ñ -phenylazatriene用二甲基乙烯酮或二氯乙烯酮仅产生的[2 + 2] cycloadducts,而反应Ñ-(二甲基氨基)氮杂三烯与二氯乙烯烯不加热得到[4 + 2]环加合物。当[2 + 2]环加合物在β-内酰胺环的C-4具有两个不同的乙烯基取代基时,重排的区域选择性取决于空间因素和取代基的电子需求。最初的[4 + 2]环加合物与缺电子的亲二烯体(TCNE,N-苯基马来酰亚胺)的第二次Diels-Alder反应立体选择性地生成六氢喹啉酮衍生物。同样,氮杂-D