Absolute helicities of twisted 9,10-phenanthrenequinones.
作者:Rainer Fritsch、Erwin Hartmann、Gert Brandl、Albrecht Mannschreck
DOI:10.1016/s0957-4166(00)86088-7
日期:1993.3
non-planar 9,10-phenanthrenequinone (−)546- was determined to be (M) by a four-step chemical correlation (Scheme 2) to the bridged biphenyl (−)365-, the (M) helicity of which was proven via the circular dichroism of the conjugation band. The last step of the correlation consisted of the acyloin condensation of the diphenic ester (−)365-(M)-, during which partial loss of optical purity was observed. An intermediate
( - )非平面9,10-菲醌的绝对构型546 -被确定为(M)由一个四步化学相关性(方案2)的桥连联苯( - )365 -中,(M)通过共轭带的圆二色性证明了其螺旋性。的相关性的最后一步包括在联苯酯的酮醇缩合的( - )365 - (M) -,在此期间观察到光学纯度的部分损失。中间体9,10-双(三甲基甲硅烷氧基)菲被认为以适度的速率消旋,从而导致一些活性损失。扭曲的9,10-菲醌的相对构型可以通过在Ca 2+之间的一系列弱Cotton效应来确定。370和500 nm(表2和3)。这些对于(M)醌是阴性的,如上述与桥联联苯的相关性所示。光学活性吸附剂的液相色谱可用于大多数对映异构体的半制备分离和对映体纯度的测定。