- Precursor reaction kinetics control compositional grading and size of CdSe1-: XSx nanocrystal heterostructures
-
We report a method to control the composition and microstructure of CdSe1-xSx nanocrystals by the simultaneous injection of sulfide and selenide precursors into a solution of cadmium oleate and oleic acid at 240 °C. Pairs of substituted thio- and selenoureas were selected from a library of compounds with conversion reaction reactivity exponents (kE) spanning 1.3 × 10-5 s-1 to 2.0 × 10-1 s-1. Depending on the relative reactivity (kSe/kS), core/shell and alloyed architectures were obtained. Growth of a thick outer CdS shell using a syringe pump method provides gram quantities of brightly photoluminescent quantum dots (PLQY = 67 to 90%) in a single reaction vessel. Kinetics simulations predict that relative precursor reactivity ratios of less than 10 result in alloyed compositions, while larger reactivity differences lead to abrupt interfaces. CdSe1-xSx alloys (kSe/kS = 2.4) display two longitudinal optical phonon modes with composition dependent frequencies characteristic of the alloy microstructure. When one precursor is more reactive than the other, its conversion reactivity and mole fraction control the number of nuclei, the final nanocrystal size at full conversion, and the elemental composition. The utility of controlled reactivity for adjusting alloy microstructure is discussed.
- Hamachi, Leslie S.,Yang, Haoran,Jen-La Plante, Ilan,Saenz, Natalie,Qian, Kevin,Campos, Michael P.,Cleveland, Gregory T.,Rreza, Iva,Oza, Aisha,Walravens, Willem,Chan, Emory M.,Hens, Zeger,Crowther, Andrew C.,Owen, Jonathan S.
-
p. 6539 - 6552
(2019/07/10)
-
- Cyclopalladation of azobenzenes and their reactivity towards N-substituted imidazolidine-2-thiones and allied ligands: Synthesis, structures, spectroscopy and ESI-mass studies
-
Reactions of palladium(II) chloride with azobenzene (azbH), p-methoxyazobenzene (mazbH) and 4, 4′-diethoxyazobenzene (deazbH) in methanol yielded halogen bridged dinuclear precursors [Pd2(κ2:C,N-L)2(μ-Cl)2] (here L = azb?, mazb? and deazb?). These precursors were further reacted with a series of N, S- donor thio-ligands, namely, 1,3-imidazolidine-2-thiones (imdzSH-NR; R = H, Me, Et, Prn, Bun, Ph), N-methyl-imidazoline-2-thione (imzSH-NMe), 1,3-benzimidazoline-2-thione (bzimSH-NH) and 1, 3- thiazolidine-2-thione (tzdSH). Nineteen dinuclear organometallic compounds synthesized are listed as follows: (a) [Pd2(κ2:C, N-azb)2(μ-N, S-imdzS-NR)2] (R = H, 1; Me, 2; Et 3; Prn 4; Bun 5; Ph 6), (b) [Pd2(κ2:C, N-mazb)2(N, S-imdzS-NR)2] (R = Me, 7; Et, 8; Prn 9; Bun 10), (c) [Pd2(κ2:C, N-deazb)2(N, S-imdzS-NR)2] (R = Et, 11; Prn 12; Bun 13; Ph 14), (d) [Pd2(κ2:C, N-azb)2(μ-N, S-L)2] (L = bzimS-NH 15; imzS-NMe 16; tzdS 17), and (e) [Pd2(κ2:C, N-deazb)2(N, S-L)2] (L = bzimS-NH 18; imzS-NMe 19). All these compounds have been characterized with the help of analytical data, electron absorption, NMR and fluoresecence spectroscopy, ESI-mass spectrometry and single crystal X-ray crystallography. The loss of one C-H proton of an azobenzene and one N-H proton of a thio-ligand occurred per palladium metal center in dinuclear complexes synthesized, which have C, N-chelating azobenzenes and N, S-bridging heterocyclic thiolates.
- Sandhu, Amanpreet K.,Lobana, Tarlok S.,Sran, Balkaran S.,Hundal, Geeta,Jasinski, Jerry P.
-
p. 112 - 124
(2018/03/06)
-
- Synthesis of Isothiocyanates and Unsymmetrical Thioureas with the Bench-Stable Solid Reagent (Me4N)SCF3
-
A highly efficient, selective, and rapid transformation of primary amines and diamines to isothiocyanates and cyclic thioureas is disclosed. As opposed to established approaches that employ toxic or volatile electrophilic liquids and require reaction control (i.e., slow addition, cooling), this protocol utilizes the bench-stable, solid reagent (Me4N)SCF3 at room temperature. The method is characterized by operational simplicity, high speed, efficiency, high functional group tolerance, and late-stage applicability. The byproducts are solids, allowing isolation of the target compounds by filtration.
- Scattolin, Thomas,Klein, Alexander,Schoenebeck, Franziska
-
supporting information
p. 1831 - 1833
(2017/04/11)
-
- Synthesis, Spectroscopy, and Structures of Mono- and Dinuclear Copper(I) Halide Complexes with 1,3-Imidazolidine-2-thiones
-
Copper(I) halides with triphenyl phosphine and imidaozlidine-2-thiones (L-NMe, L-NEt, and L-NPh) in acetonitrile/methanol (or dichloromethane) yielded copper(I) mixed-ligand complexes: mononuclear, namely, [CuCl(κ1-S-L-NMe)(PPh3)2] (1), [CuBr(κ1-S-L-NMe)(PPh3)2] (2), [CuBr(κ1-S-L-NEt)(PPh3)2] (5), [CuI(κ1-S-L-NEt)(PPh3)2] (6), [CuCl(κ1-S-L-NPh)(PPh3)2] (7), and [CuBr(κ1-S-L-NPh)(PPh3)2] (8), and dinuclear, [Cu2(κ1-I)2(μ-S-L-NMe)2(PPh3)2] (3) and [Cu2(μ-Cl)2(κ1-S-L-NEt)2(PPh3)2] (4). All complexes were characterized with analytical data, IR and NMR spectroscopy, and X-ray crystallography. Complexes 2-4, 7, and 8 each formed crystals in the triclinic system with Pβar{1}$ space group, whereas complexes 1, 5, and 6 crystallized in the monoclinic crystal system with space groups P21/c, C2/c, and P21/n, respectively. Complex 2 has shown two independent molecules, [(CuBr(κ1-S-L-NMe)(PPh3)2] and [CuBr(PPh3)2] in the unit cell. For X = Cl, the thio-ligand bonded to metal as terminal in complex 4, whereas for X = I it is sulfur-bridged in complex 3.
- Walia, Simran,Kaur, Supreet,Kaur, Jaspreet,Sandhu, Amanpreet K.,Lobana, Tarlok S.,Hundal, Geeta,Jasinski, Jerry P.
-
p. 1728 - 1736
(2015/08/18)
-
- INHIBITORS OF PROTEIN TYROSINE KINASE ACTIVITY
-
The invention relates to compounds of Formula (I) and their use for inhibiting protein tyrosine kinase activity In Formula (I), the group M is thieno[3,2,b]pyridinyl as shown, and the group D is a ring or ring system, and the groups Z, Ar, and G are as defined herein The invention relates particularly to compounds that inhibit the protein tyrosine kinase activity of growth factor receptors, resulting in the inhibition of receptor signalling, for example, the inhibition of VEGF receptor signalling and HGF receptor signalling The invention also provides compositions and methods for treating cell proliferative diseases and conditions, such as cancer, and for treating ophthalmic diseases, including age-related macular degeneration (AMD) and diabetic retinopathy (DR)
- -
-
Page/Page column 144-145
(2009/04/25)
-
- Solid-phase synthesis of 2-imidazolidinethiones via Mitsunobu reaction of N-(2-hydroxyethyl)thioureas
-
This letter reports the solid-phase synthesis of 2-imidazolidinethiones via the N-cyclization of N-(2-hydroxyethyl)thioureas using the Mitsunobu reaction in good yield and purity. This process employed the reductive amination of an ArgoGel-MB-CHO resin to
- Jeon, Hyun Suk,Yoo, Je Hwa,Kim, Jae Nyoung,Kim, Taek Hyeon
-
p. 439 - 441
(2008/02/03)
-
- Synthesis of imidazoline and imidazo[2,1-c][1,2,4]triazole aryl derivatives containing the methylthio group as possible antibacterial agents
-
1-Arylimidazolidine-2-thiones (1a-g) were synthesized by the condensation reaction of N-arylethylenediamines with carbon disulfide in xylene medium. Their further alkylation with methyl iodide led to the formation of some biologically active 1-aryl-2-meth
- Sztanke, Krzysztof,Pasternak, Kazimierz,Sidor-Wójtowicz, Anna,Truchlińska, Janina,Jó?wiak, Krzysztof
-
p. 3635 - 3642
(2007/10/03)
-
- Design, synthesis, and pharmacological evaluation of conformationally constrained analogues of N,N'-diaryl- and N-aryl-N-aralkylguanidines as potent inhibitors of neuronal Na+ channels
-
In the present investigation, the rationale for the design, synthesis, and biological evaluation of potent inhibitors of neuronal Na+ channels is described. N,N'-Diaryl- and N-aryl-Naralkylguanidine templates were locked in conformations mimick
- Maillard, Michel C.,Perlman, Michael E.,Amitay, Oved,Baxter, Deborah,Berlove, David,Connaughton, Sonia,Fischer, James B.,Guo, Jun Qing,Hu, Lain-Yen,McBurney, Robert N.,Nagy, Peter I.,Subbarao, Katragadda,Yost, Elizabeth A.,Zhang, Lu,Durant, Graham J.
-
p. 3048 - 3061
(2007/10/03)
-