作者:Harish R. Talele、Sibaprasad Sahoo、Ashutosh V. Bedekar
DOI:10.1021/ol301267r
日期:2012.6.15
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 theta (similar to 12 degrees), while the units attached to [4]helicene showed a larger theta (similar to 35 degrees) 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.