作者:Wanchai Pluempanupat、Michael Abraham、Lothar Brecker、Peter Wolschann、Alfred Karpfen、Vladimir B. Arion、Michael Widhalm
DOI:10.1021/jo200089p
日期:2011.5.6
separable, rotamers were isolated and characterized by NMR spectroscopy and X-ray structure determination. Their interconversion (process I) was followed by NMR, yielding rate constants and thermodynamic parameters. The rotamers with either C1 or C2 symmetry were stereospecifically cyclized to conformatively moderately stable bis-sulfonamides. Also in this case, the kinetics of their interconversion
在2,2'-二羟基-1,1'-联萘和2,2'-二氨基-1,1'-联萘中分别桥接2,3和2',3'位置,导致形成手性O-和N-双三环化合物可从已知的3,3'-二碘代前体以4步访问。在这两种情况下,四烯丙基中间体的2-折叠开环易位区域选择性地分别产生四氢联萘并[2,3- b ]氧杂平和-氮杂平。在N-甲磺酰基-N-烯丙基前体的情况下,在室温下可分离出三个,通过NMR光谱和X射线结构测定来表征其旋转异构体。他们的相互转化(过程I)之后是NMR,产率常数和热力学参数。具有C 1或C 1的旋转器C 2对称立体定向到构象适度稳定的双磺酰胺。同样在这种情况下,研究了它们相互转化的动力学(过程Ⅱ),并从其中两个确定了晶体结构。通过DFT方法M06-2X对方法I和II进行了研究,以深入了解造成显着构象稳定性的电子和位阻特性。计算了过渡态的几何形状和能量,并将其与经验数据进行了比较。