A Fragment-Based Approach toward Substituted Trioxa[7]helicenes
摘要:
A series of novel substituted trioxa[7]helicenes have been successfully prepared by a one-pot palladium catalyzed C-H arylation reaction starting from readily prepared dibenzofuran fragments. The dinitro-substituted helicene was analyzed by X-ray crystallography revealing the occurrence of two distinct enantiomers in the asymmetric unit, which forms interesting supramolecular motifs in the crystal, based on weak H-bonding interactions.
Synthesis of Functionalized Dioxa-aza[7]helicenes Using Palladium Catalyzed Arylations
摘要:
Despite the recent reports on transition-metal catalyzed cycloisomerization strategies toward helicenes, the amount of palladium catalyzed routes remains rather scarce. Within this letter the successful preparation and characterization of novel dioxa-aza[7]helicenes using palladium mediated coupling reactions is presented.