Conformational Studies by Dynamic NMR. 86.<sup>1</sup> Structure, Stereodynamics, and Cryogenic Enantioseparation of the Stereolabile Isomers of <i>o</i>-Dinaphthylphenyl Derivatives
作者:Carlo Dell'Erba、Francesco Gasparrini、Stefano Grilli、Lodovico Lunazzi、Andrea Mazzanti、Marino Novi、Marco Pierini、Cinzia Tavani、Claudio Villani
DOI:10.1021/jo016397m
日期:2002.3.1
Static and dynamic stereochemistry of the hydrocarbon comprising a phenyl ring bearing two alpha-naphthyl substituents in the ortho positions, i.e., 1,2-di-(4-methyl-naphth-1-yl)-benzene 1, has been studied by a combination of variable temperature NMR, cryogenic HPLC, and MM calculations. Whereas in solution both syn (meso) and anti (chiral) forms were observed and the corresponding interconversion
已经通过以下方法研究了包含在邻位带有两个α-萘基取代基的苯环的烃的静态和动态立体化学,即1,2-二-(4-甲基-萘-1-基)-苯1。可变温度NMR,低温HPLC和MM计算的结合。溶液中同时观察到了顺式(间位)和反式(手性)形式,并确定了相应的互转换垒(Delta G(++)= 19.5 kcal mol(-1)),而在其中仅发现了非对映异构体anti结晶状态(X射线衍射)。当通过在苯环中引入硝基使分子不对称时,例如在1,2-二-(4-甲基-萘-1-基)-4-硝基苯2中,手性同构和反对映异构体同时存在溶液和固态都可以,尽管比例不同。