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1.
The Synthesis of B2(SIDip)2 and its Reactivity Between the Diboracumulenic and Diborynic Extremes 下载免费PDF全文
Julian Bhnke Holger Braunschweig Theresa Dellermann William C. Ewing Kai Hammond J. Oscar C. Jimenez‐Halla Thomas Kramer Jan Mies 《Angewandte Chemie (International ed. in English)》2015,54(46):13801-13805
A new compound with the formula L‐B2‐L wherein the stabilizing ligand (L) is 1,3‐bis[diisopropylphenyl]‐4,5‐dihydroimidazol‐2‐ylidene (SIDip) has been synthesized, isolated, and characterized. The π‐acidity of the SIDip ligand, intermediate between the relatively non‐acidic IDip (1,3‐bis[diisopropylphenyl]imidazol‐2‐ylidene) ligand and the much more highly acidic CAAC (1‐[2,6‐diisopropylphenyl]‐3,3,5,5‐tetramethylpyrrolidin‐2‐ylidene) ligand, gives rise to a compound with spectroscopic, electrochemical, and structural properties between those of L‐B2‐L compounds stabilized by CAAC and IDip. Reactions of all three L‐B2‐L compounds with CO demonstrate the differences caused by their respective ligands, as the π‐acidities of the CAAC and SIDip carbenes enabled the isolation of bis(boraketene) compounds (L(OC)B‐B(CO)L), which could not be isolated from reactions with B2(IDip)2. However, only B2(IDip)2 and B2(SIDip)2 could be converted into bicyclic bis(boralactone) compounds. 相似文献
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Philip J. Hammond C. Dennis Hall 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):351-353
Abstract Cis-1-alkyl (or aryl)-2,5-dimethyl-3-phospholens isomerize to the trans-isomers in deuteriochloroform and the isomerization is probably due to small quantities of phosgene in the solvent. 相似文献
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Jason F. Hammond David M. Bortz 《Applied mathematics and computation》2011,218(6):2497-2508
This paper provides analytical solutions to the generalized Fisher equation with a class of time varying diffusion coefficients. To accomplish this we use the Painlevé property for partial differential equations as defined by Weiss in 1983 in “The Painlevé property for partial-differential equations”. This was first done for the variable coefficient Fisher’s equation by Ö?ün and Kart in 2007; we build on this work, finding additional solutions with a weaker restriction on the trial solution. We also use the same technique to find solutions to Fisher’s equation with time-dependent coefficients for both diffusion and nonlinear terms. Lastly we compute specific solutions to illustrate their behaviors. 相似文献
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J. Bicskei A. Dubose E. Spitalsky S. Jofa D. Dobrosserdow F. Dienert W. S. Iofinow W. W. Scott G. G. Kandilarow D. S. Reynols W. H. Ross K. D. Jacob N. K. Smit L. D. Hammond A. Travers H. Ginsberg G. Holder B. Thèphile H. ter Meulen P. Drawe G. E. F. Lundell und J. I. Hoffmann 《Fresenius' Journal of Analytical Chemistry》1930,81(5-7):232-242
Ohne Zusammenfassung 相似文献
8.
Tatiana A. Shmigol Samantha Hammond James B. Phillips James I. Bruce Alexander J. MacRobert Mikhail V. Malakhov Jon P. Golding 《Photochemistry and photobiology》2013,89(1):139-149
Phthalocyanine photosensitizers are effective in anticancer photodynamic therapy (PDT) but suffer from limited solubility, limited cellular uptake and limited selectivity for cancer cells. To improve these characteristics, we synthesized isopropylidene‐protected and partially deprotected tetra β‐glycosylated zinc (II) phthalocyanines and compared their uptake and accumulation kinetics, subcellular localization, in vitro photocytotoxicity and reactive oxygen species generation with those of disulfonated aluminum phthalocyanine. In MCF‐7 cancer cells, one of the compounds, zinc phthalocyanine {4}, demonstrated 10‐fold higher uptake, 5‐fold greater PDT‐induced cellular reactive oxygen species concentration and 2‐fold greater phototoxicity than equimolar (9 μm ) disulfonated aluminum phthalocyanine. Thus, isopropylidene‐protected β‐glycosylation of phthalocyanines provides a simple method of improving the efficacy of PDT. 相似文献
9.
Alan Hammond 《Communications in Mathematical Physics》2012,310(2):455-509
This is the first in a series of three papers that addresses the behaviour of the droplet that results, in the percolating
phase, from conditioning the planar Fortuin-Kasteleyn random cluster model on the presence of an open dual circuit Γ0 encircling the origin and enclosing an area of at least (or exactly) n
2. (By the Fortuin-Kasteleyn representation, the model is a close relative of the droplet formed by conditioning the Potts
model on an excess of spins of a given type.) We consider local deviation of the droplet boundary, measured in a radial sense
by the maximum local roughness, MLR(Γ0), this being the maximum distance from a point in the circuit Γ0 to the boundary ∂ of the circuit’s convex hull; and in a longitudinal sense by what we term maximum facet length, MLF(Γ0), namely, the length of the longest line segment of which the polygon ∂ is formed. The principal conclusion of the series of papers is the following uniform control on local deviation: that there
are constants 0 < c < C < ∞ such that the conditional probability that the normalized quantity n
−1/3(log n )−2/3MLR lies in the interval [c, C] tends to 1 in the high n-limit; and that the same statement holds for n
−2/3 (log n )−1/3 MLF. In this way, we confirm the anticipated n
1/3 scaling of maximum local roughness, and provide a sharp logarithmic power-law correction. This local deviation behaviour
occurs by means of locally Gaussian effects constrained globally by curvature, and we believe that it arises in many radially
defined stochastic interface models, including growth models belonging to the Kardar-Parisi-Zhang universality class. 相似文献
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