1460-59-9Relevant academic research and scientific papers
An efficient synthesis of dibenzocycloocta-4a,6a,-diene-5,11-diyne and its precursors
Chaffins, Sterling,Brettreich, Michael,Wudl, Fred
, p. 1191 - 1194 (2002)
Two efficient syntheses of dibenzocyclooctadienediyne 1 were developed employing known reactions, which utilize commercially available reagents. Both methods are an improvement on known syntheses resulting in 41% and 43% overall yields. The latter method also offers an efficient synthesis of dibenzocyclooctatetraene 9, which is one of the key reagents now commercially unavailable.
Organic Sonochemistry. Ultrasound-Promoted Reaction of Zinc with α,α'-Dibromo-o-xylene. Evidence for Facile Generation of o-Xylylene
Han, Byung Hee,Boudjouk, Philip
, p. 751 - 752 (1982)
α,α'-Dibromo-o-xylene and zinc powder react smoothly in the presence of dienophiles and sonic waves to give high yields of cycloaddition products.The reaction is belived to proceed via the reactive intermediate, o-xylylene.
Synthesis of some substituted 5,6,11,12-tetrahydro-dibenzo[a,e]cyclooctene derivatives through the intermediacy of tricarbonyl(η6 -arene)chromium complexes
Zenouz, A. Moshtaghi
, p. 2967 - 2971 (2004)
5,6,11,12-Tetrahydrodibenzo[a,e]cyclooctene derivatives with α- and β-substituents are readily accessible from [Cr(CO)3(5,6,11,12- tetrahydrodibenzo[a,e]cyclooctene)] 2 via a two-step sequence, which involves addition of a nucleophile and oxidation of the intermediate anionic cyclohexadienyl complex. Nucleophiles used included LiCMe2CN (A), LiCH2CN (B), and (C). The results show that the primary carbanion LiCH2CN and the S-stabilized carbanion give mixtures of α- and β-substituted products and in both cases α-isomers were major, whereas the opposite regioselectivity was obtained with the tertiary carbanion LiCMe2CN.
2-[(Trimethylsilyl)methyl]benzyl methanesulfonates: Useful precursors for the generation of o -quinodimethanes
Shirakawa, Hidenori,Sano, Hiroshi
, p. 1788 - 1792 (2014)
2-[(Trimethylsilyl)methyl]benzyl methanesulfonates react with potassium fluoride in the presence of a catalytic amount of 18-crown-6 at room temperature to give o-quinodimethanes, which are trapped with electron-deficient olefins to afford [4+2] cycloadducts in good yields. Georg Thieme Verlag Stuttgart New York.
Potassium fluoride-induced 1,4-elimination of o-[(trimethylsilyl)methyl] benzyl acetates: A versatile generation of o-quinodimethanes
Kuwano, Ryoichi,Shige, Takenori
, p. 728 - 729 (2005)
o-Quinodimethane interemediate was generated from o-[(trimethylsilyl) methyl]benzyl acetate with potassium fluoride. The o-quinodimethane in hand reacted with electron-deficient olefins, affording [4+2] cycloadducts, tetrahydronaphthalenes. Copyright
Crosslinked Polymers with Tunable Coefficients of Thermal Expansion
-
Paragraph 0012; 0025, (2021/12/30)
Curatives and their resulting thermosets and other crosslinked polymers can reduce thermal expansion mismatch between an encapsulant and objects that are encapsulated. This can be accomplished by incorporating a negative CTE moiety into the thermoset resin or polymer backbone. The negative CTE moiety can be a thermal contractile unit that shrinks as a result of thermally induced conversion from a twist-boat to chair or cis/trans isomerization upon heating. Beyond CTE matching, other potential uses for these crosslinked polymers and thermosets include passive energy generation, energy absorption at high strain rates, mechanophores, actuators, and piezoelectric applications.
Iridium-Triggered Allylcarbamate Uncaging in Living Cells
Singh, Neelu,Gupta, Ajay,Prasad, Puja,Mahawar, Pritam,Gupta, Shalini,Sasmal, Pijus K.
supporting information, p. 12644 - 12650 (2021/09/06)
Designing a metal catalyst that addresses the major issues of solubility, stability, toxicity, cell uptake, and reactivity within complex biological milieu for bioorthogonal controlled transformation reactions is a highly formidable challenge. Herein, we report an organoiridium complex that is nontoxic and capable of the uncaging of allyloxycarbonyl-protected amines under biologically relevant conditions and within living cells. The potential applications of this uncaging chemistry have been demonstrated by the generation of diagnostic and therapeutic agents upon the activation of profluorophore and prodrug in a controlled fashion within HeLa cells, providing a valuable tool for numerous potential biological and therapeutic applications.
Photo-catalytic preparation method of bibenzyl compounds
-
Paragraph 0072-0075; 0072-0075; 0078, (2020/02/27)
The invention relates to a preparation method of bibenzyl compounds. A compound represented by a formula (A) and a compound represented by a formula (C) carry out reactions under the action of an organic tungsten catalyst and an alkali in the presence of light to generate bibenzyl compounds represented by the formula (B). The method is simple and is easy to operate. The yield is high, and the application range is wide. Moreover, the invention also provides an application of a tungsten complex in organic chemical reactions as a photocatalyst.
Mechanism of the Bis(imino)pyridine-Iron-Catalyzed Hydromagnesiation of Styrene Derivatives
Neate, Peter G. N.,Greenhalgh, Mark D.,Brennessel, William W.,Thomas, Stephen P.,Neidig, Michael L.
supporting information, p. 10099 - 10108 (2019/07/04)
Iron-catalyzed hydromagnesiation of styrene derivatives offers a rapid and efficient method to generate benzylic Grignard reagents, which can be applied in a range of transformations to provide products of formal hydrofunctionalization. While iron-catalyzed methodologies exist for the hydromagnesiation of terminal alkenes, internal alkynes, and styrene derivatives, the underlying mechanisms of catalysis remain largely undefined. To address this issue and determine the divergent reactivity from established cross-coupling and hydrofunctionalization reactions, a detailed study of the bis(imino)pyridine iron-catalyzed hydromagnesiation of styrene derivatives is reported. Using a combination of kinetic analysis, deuterium labeling, and reactivity studies as well as in situ 57Fe M?ssbauer spectroscopy, key mechanistic features and species were established. A formally iron(0) ate complex [iPrBIPFe(Et)(CH2a?CH2)]- was identified as the principle resting state of the catalyst. Dissociation of ethene forms the catalytically active species which can reversibly coordinate the styrene derivative and mediate a direct and reversible β-hydride transfer, negating the necessity of a discrete iron hydride intermediate. Finally, displacement of the tridentate bis(imino)pyridine ligand over the course of the reaction results in the formation of a tris-styrene-coordinated iron(0) complex, which is also a competent catalyst for hydromagnesiation.
A Manganese Nanosheet: New Cluster Topology and Catalysis
Chakraborty, Uttam,Reyes-Rodriguez, Efrain,Demeshko, Serhiy,Meyer, Franc,Jacobi von Wangelin, Axel
supporting information, p. 4970 - 4975 (2018/03/28)
While the coordination chemistry of monometallic complexes and the surface characteristics of larger metal particles are well understood, preparations of molecular metallic nanoclusters remain a great challenge. Discrete planar metal clusters constitute nanoscale snapshots of cluster growth but are especially rare owing to the strong preference for three-dimensional structures and rapid aggregation or decomposition. A simple ligand-exchange procedure has led to the formation of a novel heteroleptic Mn6 nanocluster that crystallized in an unprecedented flat-chair topology and exhibited unique magnetic and catalytic properties. Magnetic susceptibility studies documented strong electronic communication between the manganese ions. Reductive activation of the molecular Mn6 cluster enabled catalytic hydrogenations of alkenes, alkynes, and imines.
