PC 10

POLYMER-LIKE LONG GLASSY STATE MEDIATED BY SELF-ASSEMBLIES OF DIMERIC DISCOTIC LC

C.W. Ong, M.-C. Tzeng, S.-C. Liao

Department of Chemistry, National Sun Yat Sen University, Kaoshiung, TAIWAN 804. (cong@mail.nsysu.edu.tw)

Discotic LCs are being recognized for their potential applications in photovoltaic devices, field effect transistors (FETs), light emitting diodes (LEDs) and other molecular electronics.³ Some of the most prominent discotic LCs range from the most widely investigated triphenylenes,⁴ to porphyrins,⁵ phthalocyanines,⁵ hexaazatriphenylenes,^6-8 perylenes,⁹ dibenzopyrenes,¹⁰ hexabenzocoronenes,^11,12 dibenzoquinoxa-lines¹³ and dibenzo[a,c]phenazine.¹⁴

Discotic LCs are being considered for their potential applications in photovoltaic devices, field effect transistors, light emitting diodes and other molecular electronics. Many wide array of single disc compounds have been widely investigated, such as the triphenylenes, porphyrins, phthalocyanines, hexaazatriphenylenes, perylenes, dibenzopyrenes, hexabenzocoroneses, dibenzoquinoxalines and dibenzo{a,c}phenazines. Although self assembled into columns during the mesophase(s), the order is lost after crystallization. Thus, for application, there is a need to synthesize discotic LC with room temperature mesophase.

In order to overcome this problem, much research has been carried out to synthesize polymeric discotic LC, but they have their disadvantages. Recently, the focus has turned to the synthesis of dimeric dicotic LCs that possesses polymeric properties. Here we report the first synthesis of a long glassy state (>10 months) dimeric discotic LC based on dibenzo{a,c}phenazines and more important this compound is not white but orange in color.