The Rich Chemistry of Cyclotriveratrylene (CTV) And CT-Inspired Reactions: Anthracenes with Organic Light-Emitting Diode (OLED) Applications and the Discovery of Cascade Reactions

Cyclotriveratrylene (CTV) is a supramolecular scaffold with applications in host-guest chemistry, analytical detection, drug delivery and liquid crystals. We have discovered that CTV rearranges to a highly functionalized anthracene derivative that is ideal for the synthesis of 9,10-disubstituted anthracene derivatives that are useful for the construction of organic light-emitting diodes (OLEDs). Several diaryl anthracene derivatives have been synthesized and analyzed, and were found to have excellent electroluminescent properties, including one analog that exhibits an exceptionally high quantum yield. Red, green and blue are the primary colors needed for full color display, but blue fluorescence emitting organic compounds used in OLEDs degrade rapidly and do not last long due to the high energy required for blue fluorescence emission. Most of the recent research in OLED compounds has been focused on finding a compound that will be an ideal candidate for the construction of blue OLEDs. Further, while exploring the chemistry of CTV, we have also discovered cascade reaction sequences, where one reaction sets up the subsequent reaction in a domino fashion, enabling the construction of highly complex molecules in a synthetic single operation. We have discovered that CTV undergoes a dual reaction sequence involving a Beckmann rearrangement followed by an electrophilic aromatic addition, two classic reactions that have never been seen combined into a powerful tandem sequence, enabling the direct construction of ketones, imines, or amines simply through varying the reaction conditions. We have now demonstrated that this tandem reaction sequence is general through success with a series of substrates. Finally, while exploring this Tandem Beckmann sequence, an even more useful cascade reaction was discovered involving the Beckmann reaction, followed by a Ritter reaction, and finally an electrophilic aromatic substitution. This triple cascade reaction sequence affords pharmaceutically important quinazolines and is presently being explored for its generality with very encouraging results