Department of Chemistry, Faculty of Science, M.S. University of Baroda, Vadodara 390 002, India.
Org Lett. 2012 Jun 15;14(12):3166-9. doi: 10.1021/ol301267r. Epub 2012 Jun 6.
A series of novel 1,3-oxazines were prepared to construct a helical framework. The 1,3-oxazine attached to the phenanthrene unit showed a small bite angle θ (∼12°), while the units attached to [4]helicene showed a larger θ (∼35°) and exhibited helical isomers at ambient conditions. The diastereomers of the third type of helicene-like bis-oxazine attached to binaphthyl were easily separable and showed good thermal stability. All four diastereomers of bis-helicene were synthesized, and their absolute configuration was established.
一系列新型 1,3-恶嗪被制备来构建一个螺旋骨架。连接到菲单元的 1,3-恶嗪显示出一个小的夹角θ（约 12°），而连接到[4]螺旋烯的单元则显示出更大的θ（约 35°），并在环境条件下表现出螺旋异构体。连接到联萘的第三种类似螺旋烯的双恶嗪的非对映异构体很容易分离，并表现出良好的热稳定性。双螺旋烯的所有四个非对映异构体都被合成，并确定了它们的绝对构型。
