Synthesis and Applications of Novel Green Dopants for Organic Light Emitting Devices

• Main Authors: Lee Meng Ting, 李孟庭
• Other Authors: Chen Chin Hsin
• Format: Others
• Language: zh-TW
• Published: 2002
• Online Access: http://ndltd.ncl.edu.tw/handle/82598088987754918511

碩士 === 國立交通大學 === 應用化學系 === 90 === We have discovered a new family of green fluorescent dopants based on coumarin structure --- ethyl-1,1,5,5,7-pentamethyl-11-oxo-2,3,6,7-tetrahydro- 1H,5H,11H-pyrano[2,3-f]pyrido[3,2,1-ij]quinoline-10-carboxylate (C-314P)；10-acetyl-1,1,5,5,7-pentamethyl-2,3,6,7-tetrahydro-1H,5H,11H-pyrano[2,3-f]- pyrido[3,2,1-ij]-quinolin-11-one (C-334P)；1,1,5,5,7-pentamethyl-10- (phenylsulfonyl)-2,3,6,7-tetrahydro-1H,5H,11H-pyrano[2,3-f]pyrido[3,2,1-ij]quinolin-11-one (C-340P)；10-(1,3-benzothiazol-2-yl)-1,1,5,5,7-pentamethyl- 2,3,6,7-tetrahydro-1H,5H,11H-pyrano[2,3-f]pyrido[3,2,1-ij]quinolin-11-one (C-545P)；10-[5,7-di(tert-butyl)-1,3-benzothiazol-2-yl]-1,1,5,5,7-pentamethyl- 2,3,6,7-tetrahydro-1H,5H,11H-pyrano[2,3-f]pyrido[3,2,1-ij]quinolin-11-one (C-545PB) and 1,1,5,5,7-pentamethyl-10-naphtho[1,2-d][1,3]-oxazol-2-yl- 2,3,6,7-tetrahydro-1H,5H,11H-pyrano[2,3-f]pyrido[3,2,1-ij]quinolin-11-one (C-520P). The molecular design of this new family of dopants, is based on five (penta) strategically placed “methyl” steric spacers as contrasted to 10-(2-benzothiazolyl)-1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H,11H- benzo[l]pyrano[6,7,8-ij]quinolizin-11-one (C-545T) which only has four (tetra). The “P” family of dopants has the unique feature of having two gem-dimethyl groups situated alpha (a) to the nitrogen of the julolidine bearing the lone pair p-orbital. From the perspective of stereochemistry, the lack of molecular symmetry in the pattern of methyl substitution on julolidyl ring is expected to prevent molecular aggregation and delay the onset of quenching at high doping concentration as well.When fabricated as doped emitter in Alq3 hosted OLED devices, they show significant improvement in thermal properties, luminance efficiency and resistance to concentration quenching over the commercial dopant C-545T.