13389-72-5Relevant academic research and scientific papers
Dications of fluorenylidenes. The relationship between redox potentials and antiaromaticity for meta- and para-substituted diphenylmethylidenefluorenes
Mills, Nancy S.,Tirla, Cornelia,Benish, Michele A.,Rakowitz, Amber J.,Bebell, Lisa M.,Hurd, Caroline M. M.,Bria, Anna L. M.
, p. 10709 - 10716 (2005)
Electrochemical oxidation of meta-substituted diphenylmethylidenefluorenes (3a-g) results in the formation of fluorenylidene dications that are shown to be antiaromatic through calculation of the nucleus independent chemical shift (NICS) for the 5- and 6-
Catalyst- And Silane-Controlled Enantioselective Hydrofunctionalization of Alkenes by Cobalt-Catalyzed Hydrogen Atom Transfer and Radical-Polar Crossover
Ebisawa, Kousuke,Izumi, Kana,Ooka, Yuka,Kato, Hiroaki,Kanazawa, Sayori,Komatsu, Sayura,Nishi, Eriko,Shigehisa, Hiroki
supporting information, p. 13481 - 13490 (2020/09/02)
The catalytic enantioselective synthesis of tetrahydrofurans, which are found in the structures of many biologically active natural products, via a transition-metal-catalyzed hydrogen atom transfer (TM-HAT) and radical-polar crossover (RPC) mechanism is described herein. Hydroalkoxylation of nonconjugated alkenes proceeded efficiently with excellent enantioselectivity (up to 94% ee) using a suitable chiral cobalt catalyst, N-fluoro-2,4,6-collidinium tetrafluoroborate, and diethylsilane. Surprisingly, the absolute configuration of the product was highly dependent on the steric hindrance of the silane. Slow addition of the silane, the dioxygen effect on the solvent, thermal dependence, and DFT calculation results supported the unprecedented scenario of two competing selective mechanisms. For the less-hindered diethylsilane, a high concentration of diffused carbon-centered radicals invoked diastereoenrichment of an alkylcobalt(III) intermediate by a radical chain reaction, which eventually determined the absolute configuration of the product. On the other hand, a more hindered silane resulted in less opportunity for a radical chain reaction, instead facilitating enantioselective kinetic resolution during the late-stage nucleophilic displacement of the alkylcobalt(IV) intermediate.
Photo-induced phosphorus radical involved semipinacol rearrangement reaction: Highly synthesis of γ-oxo-phosphonates
Wang, Chunhai,Huang, Xiaoling,Liu, Xueting,Gao, Suqian,Zhao, Bin,Yang, Shangdong
supporting information, p. 677 - 680 (2019/08/27)
Hydroxyphosphoric acids display the unique biological activities, and they have some attractive prospects as clinical drug moleculars. Herein, a new approach for the synthesis of γ-oxo-phosphonates (the precursor of hydroxyphosphoric acid) has been established through the semipinacol rearrangement tactic involved the photo-induced phosphorus radical process. Most important, this transformation is avoid of the external oxidants, and occurs very well under the sunlight irradiation, meanwhile the γ-oxo-phosphonate was easily derivatized to obtain γ-hydroxyphosphoric acid, thus highlights the synthesis value of this method.
Co(III)-Catalyzed Synthesis of Quinazolines via C-H Activation of N-Sulfinylimines and Benzimidates
Wang, Fen,Wang, He,Wang, Qiang,Yu, Songjie,Li, Xingwei
supporting information, p. 1306 - 1309 (2016/04/01)
C-H activation of arenes has been established as an important strategy for heterocycle synthesis via annulations between arenes and unsaturated coupling partners. However, nitriles failed to act as such a coupling partner. Dioxazolones have been employed as a synthon of nitriles, and subsequent coupling with arenes such as N-sulfinylimines and benzimidates bearing a functionalizable directing group provided facile access to two classes of quinazolines under Co(III)-catalysis.
6-azabicyclo[3.2.1]octanes via copper-catalyzed enantioselective alkene carboamination
Casavant, Barbara J.,Hosseini, Azade S.,Chemler, Sherry R.
supporting information, p. 2697 - 2702 (2014/09/29)
Bridged bicyclic rings containing nitrogen heterocycles are important motifs in bioactive small organic molecules. An enantioselective copper-catalyzed alkene carboamination reaction that creates bridged heterocycles is reported herein. Two new rings are
MODULATORS OF C3A RECEPTOR AND METHODS OF USE THEREOF
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Page/Page column 102, (2008/12/07)
Provided are compounds that are modulators of C3a receptor activity, compositions containing the compounds and methods of use of the compounds and compositions. In certain embodiments, the compounds are pyridones. In certain embodiments, provided are methods for treatment or amelioration of diseases associated with modulation of C3a receptor activity.
Stabilities of Carbonium Ions. IV. Steric Effects in the Solvolysis of Substituted Diphenylmethyl Chlorides
Bolton, Roger,Burley, Rita E.,Williams, Nigel J.
, p. 625 - 634 (2007/10/02)
The replacement of ortho-hydrogen atoms by methyl groups in diphenylmethyl chloride has three distinguishable results upon the rate of solvolysis.Firstly, the alkyl group activates by its electronic effect; secondly, steric interactions diminish all obsse
Carbon Acidity. 66. Equilibrium Ion Pair Acidities of Substituted Diphenylmethanes in Cyclohexylamine
Streitwieser, Andrew Jr.,Vorpagel, Erich R.,Chen, Chia-Chung
, p. 6970 - 6975 (2007/10/02)
The pKCsCHA values are reported for a number of symmetrically meta- and para-substituted diphenylmethanes.The pKCsCHA values for the meta series (Me, 33.8; OMe, 32.7; F, 29.9; CF3, 28.9; Ph, 32.3; H, 33.4) give a normal Hammett plot with ρ = 9.69.The para series (Me, 35.1; OMe,37.6; Ph, 30.8; NMe2, 38.6; SPh, 28.8; CN, 23.0; SO2Me, 22.4) do not fit attempted correlations with ?, the Yukawa-Tsuno modifications, or dual substituent parameter approaches.Electron-donating groups are more anion destabilizing than in other reference systems. "Amphoteric" substituents, those that stabilize both anions and cations (phenyl, thio, etc.), cause special problems in generalized correlations.
