- OXIDATIVE FORMYLATION AND CHLOROMETHYLATION AS ALTERNATIVE PATHWAYS TO CHLOROFORMYLATION IN THE REACTION OF O- AND S-HETEROCYCLIC KETONES WITH DIMETHYLFORMAMIDE-PHOPHORUSOXYCHLORIDE
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The action of DMF-POCl3 at 20 deg C on tetrahydro-4H-pyran-4-one, tetrahydro-4H-thiopyran-4-one, chroman-4-one, and thiochroman-4-one affords the corresponding β-chlorovinylaldehydes, whereas with excess DMF-POCl3 at 100 deg C chroman-4-one affords 3-(chloromethyl)chromone, and thiochromanone gives 3-formylthiochromone.
- Giles, Paul R.,Marson, Charles M.
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- Design of thermally activated delayed fluorescent emitters for organic solid-state microlasers
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A small energy gap between charge transfer (CT) singlet and triplet states enables thermally activated delayed fluorescence (TADF). Nevertheless, the small oscillator strength associated with CT states and their long exciton lifetimes are detrimental to establishing a population inversion for stimulated emission (SE), hindering the application of a TADF material in organic lasers. Here, we demonstrated that a TADF molecule of sulfide-substituted difluoroboron derivatives can achieve stimulated emission in microcrystals by employing a new molecular design, in which an ultrafast reverse intersystem crossing (RISC) process was achieved between a hybrid locally excited CT (HLECT) singlet S1and a high-lying triplet T2(3HLECT) state. Femtosecond transient abaorption and time-reolved PL spectra reveal that the two states of S1and T2equilibrate within a time of 180 ps. In addition, the energetic spacing of ΔES1-T2= 0.11 eV enables delayed fluorescence involving the T2state at room temperature. Besides, the extremely fast exciton lifetime (0.31 μs) that decreases the probability of carrier annihilation, the HLECT singlet provides larger oscillator strength and therefore larger SE cross-section than those of the CT state. A multimode TADF laser was realized based on the good optical feedback (cavity quality factorQ≈ 2000) provided by Fabry Perot (FP) microcrystal microcavity. Our results not only confirm that the high-lying Tnstate plays a key role in the RISC process of TADF, but also provides a design of TADF gain materials.
- Fu, Hongbing,Geng, Hua,Hu, Wenping,Jin, Xue,Li, Shuai,Liao, Qing,Liao, Yi,Wu, Yishi,Xiao, Xiaoxiao,Yu, Zhenyi
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- 4H-Thieno[3,2-c]chromene based inhibitors of Notum Pectinacetylesterase
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A group of small molecule thienochromenes inhibitors of Notum Pectinacetylesterase are described. We developed SAR on three series based on carbon, oxygen and sulfur replacement of the 5-position. In each series, highly potent Notum Pectinacetylesterase inhibitors were identified.
- Han, Qiang,Pabba, Praveen K.,Barbosa, Joseph,Mabon, Ross,Healy, Jason P.,Gardyan, Michael W.,Terranova, Kristen M.,Brommage, Robert,Thompson, Andrea Y.,Schmidt, James M.,Wilson, Alan G.E.,Xu, Xiaolian,Tarver, James E.,Carson, Kenneth G.
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p. 1184 - 1187
(2016/02/23)
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- SUBSTITUTED SULFONE-CONTAINING TRICYCLIC COMPOUNDS AND USES THEREOF
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The present invention relates to substituted sulfone-containing tricyclic compounds and analogues thereof which inhibit Bak-mediated apoptosis. The invention further relates to pharmaceutical compositions comprising a compound of the present invention and to methods of inhibiting a Bak-mediated apoptotic pathway and Bak-mediated apoptosis in a cell.
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Page/Page column 32
(2014/05/24)
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- β-Iminoenamine-BF2 complexes: Aggregation-induced emission and pronounced effects of aliphatic rings on radiationless deactivation
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The synthesis, photophysical, and electrochemical attributes of a novel class of boron difluorides containing an aromatic-fused alicyclic/hetero- alicyclic ring built on a β-iminoenamine chromophoric backbone are reported. The compounds displayed large Stokes shifts (86-121 nm), and were emissive in the solid state. The quantum yields obtained in solution at room temperature were unusually lower by an order of magnitude compared to those in the solid state. Some of the tested compounds displayed aggregation-induced emission (AIE). Single crystal XRD analyses revealed a lack of interplanar π-π interactions, which are presumed to be absent owing to non-planarity of the alicyclic component in the molecule. For most of the studied compounds, time-dependent DFT (TD-DFT) calculations invariably reveal intramolecular charge transfer (π-π*) characteristics with the frontier orbitals concentrated on the boron-nitrogen heterocycle. The participation of boron and fluorine atoms was found to be negligible. Copyright
- Perumal, Karthikeyan,Garg, Jai Anand,Blacque, Olivier,Saiganesh, Ramanathan,Kabilan, Senthamaraikannan,Balasubramanian, Kallupattu Kuppusamy,Venkatesan, Koushik
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p. 2670 - 2677
(2013/01/15)
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- 4H-THIENO[3,2-C]CHROMENE-BASED INHIBITORS OF NOTUM PECTINACETYLESTERASE AND METHODS OF THEIR USE
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Compounds that may be used to inhibit Notum Pectinacetylesterase are described, as well as compositions comprising them, and methods of their use to treat diseases and disorders affecting bone.
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Page/Page column 16
(2012/12/13)
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- OXIDATIVE FORMYLATION AND CHLOROMETHYLATION IN VILSMEIER REACTIONS OF O-AND S-HETEROCYCLIC KETONES
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The action of DMF-POCl3 at 20 deg C on tetrahydro-4H-pyran-4-one, tetrahydro-4H-thiopyran-4-one, chroman-4-one, and thiochroman-4-one affords the corresponding β-chlorovinylaldehydes.However, with excess DMF-POCl3 at 100 deg C, chroman-4-one affords 3-(chloromethyl)chromone, and thiochromanone gives 3-formylthiochromone.Mechanistic rationalisations are provided.
- Giles, Paul R.,Marson, Charles M.
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p. 1303 - 1310
(2007/10/02)
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