Carbon–hydrogen bond insertion reactions of 3-acetoxy-aminoquinazolin-4(3H)-ones with cyclic dienes: stereochemistry and mechanism
作者:Robert S Atkinson、Christopher K Meades
DOI:10.1016/s0040-4020(01)01246-7
日期:2002.2
cyclohexadienyl ring carbon has been correlated with that at the 6-position of the major aziridine diastereoisomer co-produced in the reaction. A mechanism involving concerted insertion into the C–H bond of the diene by QNHOAc is proposed with endo-overlap of both double bonds of the diene with the Q group in the transition state.
2-取代的3-乙酰氧基氨基喹唑啉-4(3 H)-ones(QNHOAc)与环己-1,3-二烯或环己-1,4-二烯(2当量)的反应除了稳定的叠氮化产物外,还可以稳定通过将[QN̈:]插入双烯丙基CH键中而正式产生的二氢芳族副产物。发生类似的插入9,10-二氢蒽或v吨(1.5-2当量)的亚甲基CH键的过程。使用3- acetoxyamino -2 - [(小号)-2,2-二甲基-1-羟基丙基]喹唑啉-4(3 H ^) -酮2(Q 1在钛的存在下NHOAc)(IV)吨-丁氧基,完全非对映选择性地插入环己-1,3-二烯中,并且在环己二烯基环碳上的构型与反应中共同生成的主要氮丙啶非对映异构体的6位上的构型相关。提出了一种机制,该机制涉及通过QNHOAc一致地插入二烯的CH键中,二烯的两个双键均与Q基团处于过渡态时发生内重叠。