Electroluminiscent conjugated polymers modified with high electronegative heterocyclic moieties and their applications in polymeric light emitting diodes
strategy for the synthesis of 1,3,4-oxadiazoles was established through direct annulation of hydrazides with methylketones. It was found that the use of K2CO3 as a base achieves an unexpected and highly efficient C–C bondcleavage. This reaction is proposed to go through oxidativecleavage of Csp3–H bonds, followed by cyclization and deacylation.
通过将酰肼与甲基酮直接环合,建立了一种合成1,3,4-恶二唑的新策略。发现使用K 2 CO 3作为碱可以实现意想不到且高效的C–C键裂解。建议该反应通过C sp 3 -H键的氧化裂解,然后环化和脱酰基。
Electroluminiscent conjugated polymers modified with high eletronegative heterocyclic moieties and their applications in polymeric light emitting diodes
申请人:National Science Council Taiwan corporation
公开号:US20030109656A1
公开(公告)日:2003-06-12
This invention provides a method for syntheses of new electroluminescent conjugated polymers modified with high electronegative heterocyclic groups (such as 1,3,4-oxadiazole-diyl, 1,3,4-thiadiazole-diyl, and 1,2,4-triazole-diyl). These electroluminescent polymers (homopolymers, statistical copolymers or block coplymers) are obtained by polymerization of bis(halomethyl) arenes modified with heterocyclic groups via the Wessling precursor route, Gilch side chain route, Wittig reaction or Wittig-Hornor reaction. By a proper selection of the monomers and their ratios in the polymerization, the emissive polymers (fully conjugated or limited conjugating length) covering the full visible range even extending to the near-IR range can be prepared. The polymeric light emitting diodes (PLED) with these materials as emissive layer or electron transport layer have high external quantum efficiency and can be used as indicators and displays for cellular phones, pagers, portable computer, wristwatch, toys, etc.
provides an efficient method for the generation of diazomethyl radicals from α-diazosulfonium triflates under photochemical conditions. Utilizing the in situ generated diazomethyl radicals as key intermediate, the coupling cyclization reaction of α-diazosulfonium triflates with α-oxocarboxylic acids or alkynes has been achieved. The method affords a diverse set of important 2,5-disubstituted 1,3,4-oxadiazoles
and base-promoted dominocyclization has been disclosed for one-potsynthesis of 1,3,4-oxadiazoles via oxidative cleavage of C(sp2)-N and C(sp2)-C bonds. Herein, the use of potassium carbonate base was found to be crucial reagents in this oxidativecyclization and deacylation through selective bonds cleavage, affording mono and disubstituted 1,3,4-oxadiazoles respectively. The domino process provides