128406-10-0Relevant articles and documents
Harvesting of organic triplet emissions in metal diynes and polyynes of group 10-12 transition elements containing the conjugation-interrupting diphenylfluorene unit
Wong, Wai-Yeung,Liu, Li,Poon, Suk-Yue,Choi, Ka-Ho,Cheah, Kok-Wai,Shi, Jian-Xin
, p. 4496 - 4504 (2004)
Soluble and thermally stable group 10 platinum(II) and group 12 mercury(II) polyyne polymers containing the diphenylfluorene moiety trans-[-Pt(PBu 3)2C≡CRC≡C-]n and [-HgC≡CRC≡ C-]n (R = 9,9-diphenylfluorene) were prepared in good yields by polycondensation polymerization of trans[PtCl 2(PBu3)2] or HgCl2 with 9,9-bis(4-ethynylphenyl)fluorene. We report the optical absorption and photoluminescence spectra of these carbon-rich metal-based polymers and compare the results with their monomeric model complexes trans-[Pt(Ph)(PEt 3)2C≡CRC≡CPt(Ph)(PEt3) 2] and [MeHgC≡CRC≡CHgMe] as well as the group 11 gold(I) congener [(PPh3)AuC≡CRC≡CAu(PPh3)]. The regiochemical structures of the polymers were studied by NMR spectroscopy and by single-crystal X-ray analysis for the model platinum(II) compound. Our investigations indicate that harvesting of the organic triplet emissions can be achieved by the heavy-atom effect of group 10-12 transition metals (i.e., Pt, Au, Hg) which enables a very high efficiency of intersystem crossing from the S1 singlet excited state to the T1 triplet excited state. The influence of the metal and the fluorene ring on the intersystem crossing rate and the spatial extent of singlet and triplet excitons is characterized. These phosphorescent metal-organic materials show T1-S0 gaps of 2.5 eV or above, which correspond to S1-S0 gaps of 3.1 eV or higher. The present work indicates that high-energy triplet states (and concurrently high optical gaps) intrinsically lead to more efficient phosphorescence in metal-containing aryleneethynylenes and can facilitate the radiative decay pathway.
Synthesis of Primitive Dendrimer Systems Bearing Bicyclo[3,2,0]Hept-6-en-6-yl Groups via Unique Au-catalyzed [2+2] Cyclization
Lee, Kyu Hwan,Jillella, Raveendra,Kim, Jaewoong,Oh, Chang Ho
, p. 651 - 656 (2018/04/30)
Propargylic pivaloates bearing an alkynyl group at a three-carbon tether under the gold catalysis would undergo [3,3] rearrangements of propargylic pivaloates followed by tandem [2+2] cyclization to give the corresponding 6-acylbicyclo[3,2,0]hept-6-ens. In continuing work, we prepared various substrates bearing two arms of alkyne-propargylic pivaloates to explore primitive dendrimer concept bicyclic compounds. Finally, we could obtain a series of diasteromeric compounds bearing two arms of 6-acylbicyclo[3,2,0]hept-6-ene groups in high yields.
Fluorene-based phosphine oxide host materials for blue electrophosphorescence: An effective strategy for a high triplet energy level
Yu, Donghui,Zhao, Yongbiao,Xu, Hui,Han, Chunmiao,Ma, Dongge,Deng, Zhaopeng,Gao, Shan,Yan, Pengfei
, p. 2592 - 2596 (2011/04/12)
A bolt from the blue! Two novel host materials for blue electrophosphorescence were designed and synthesized by modification of fluorene at the 9-position with diphenylphosphine oxide to give high triplet energy levels of 2.99 eV (see scheme), achieved through an indirect linkage of the chromophore and the phosphine oxide moieties. These host materials were also found to exhibit high thermal and morphological stabilities and efficient energy transfer.
