Soluble Catalysts for Improved Pschorr Cyclizations
摘要:
Several improved catalysts for the Pschorr phenanthrene synthesis have been discovered; all are soluble substances which initiate free-radical reactions by electron donation and thereby shorten the reaction time and increase the yield. One technique with K4Fe(CN)(6) in water produced phenanthrene-9-carboxylic acid (6a) in 87% yield, but its application did not extend to substituted examples where the diazonium salt is less soluble in water. A more general procedure with ferrocene in acetone produced not only 6a but also substituted examples 6b-f in yields of 88-94%. A modification which avoids the isolation of diazonium salts was developed for occasional synthetic use.
The present invention relates to the compounds of the formula (1) and to organic electroluminescent devices, in particular blue-emitting devices, in which these compounds are used as host material in the emitting layer and/or as electron-transport material.
NOVEL MATERIALS FOR ORGANIC ELECTROLUMINESCENT DEVICES
申请人:Buesing Arne
公开号:US20100327270A1
公开(公告)日:2010-12-30
The present invention relates to the compounds of the formula (1) and to organic electroluminescent devices, in particular blue-emitting devices, in which these compounds are used as host material in the emitting layer and/or as electron-transport material.