13700-81-7Relevant academic research and scientific papers
Thermochromism of 1,2,5-triphenylphosphole and the formation of 1,1,2,2-tetrachloro-1,2-diphenylethane from α,α,α-trichlorotoluene
Hocking, Martin B.,Smyth, Trevor A.
, p. 138 - 143 (1982)
On boiling a yellow solution of 1,2,5-triphenylphosphole in carbon tetrachloride the color changes to red, reverting to yellow on cooling.This reversible colour change has been conducted in the presence of various additives in an attempt to determine the cause of the colour change.Boiling 1,2,5-triphenylphosphole in α,α,α-trichlorotoluene similarly showed a colour change and gave a coupling product of the solvent, 1,1,2,2-tetrachloro-1,2-diphenylethane.From this evidence and related synthetic, nmr, and esr experiments it is proposed that the colour change of the former system arises from the incipient formation of a phospholetrichloromethide salt with carbon tetrachloride.With trichlorotoluene the phosphole undergoes more substantive formation of dichlorophenylmethide and possibly chloride salts which undergo further reaction to the observed coupling product.
COBALOXIME(II)-INITIATED COUPLING OF α,α,α-TRIHALOMETHYLBENZENES
Stoneberger Pinault, Frances,Crumbliss, Alvin L.
, p. 229 - 239 (1981)
Bis(dimethylglyoximato) complexes of cobalt(II), cobaloxime(II), under mild conditions initiate coupling of α,α,α-trihalomethylbenzenes to form PhCX2CX2Ph (X = Cl), PhCX = CXPh (X = Cl, Br) and mixtures of halocobaloxime products.Stoichiometry, product di
Electrochemical properties and catalytic reactivity of cobalt complexes with redox-active meso -substituted porphycene ligands
Koide, Taro,Zhou, Zihan,Xu, Ning,Yano, Yoshio,Ono, Toshikazu,Luo, Zhongli,Shimakoshi, Hisashi,Hisaeda, Yoshio
, p. 90 - 97 (2020)
The cobalt complexes of meso-aryl substituted porphycenes were synthesized and characterized. The reduction potentials of the complexes were shifted to the positive side depending on the strength of the electron-withdrawing properties of the meso-substituents, while the optical properties, such as the absorption spectra of these complexes, were similar. This suggests that the energy levels of the molecular orbitals of the complexes were changed by the meso-substituents while the gaps of the orbitals were not significantly changed. The one-electron reduction of the complex did not afford the Co(I) species, but the ligand-reduced radical anion, which was characterized by electrospectrochemistry. The generated ligand-reduced species reacted with alkyl halides to form the Co(III)-alkyl complex. As a result, the reduction potential of the electrolytic reaction could be directly controlled by the substituents of the porphycene. The catalytic reaction with trichloromethylbenzene was also performed and it was found that the ratio of the obtained products was changed by the reduction potentials of the catalyst, i.e. the cobalt porphycenes.
Visible Light-Driven, One-pot Amide Synthesis Catalyzed by the B12 Model Complex under Aerobic Conditions
Tian, Hui,Shimakoshi, Hisashi,Ono, Toshikazu,Hisaeda, Yoshio
, p. 237 - 240 (2018/12/13)
A visible light responsive catalytic system with the B12 complex as the catalyst and [Ir(dtbbpy)(ppy)2]PF6 as the photosensitizer was developed. It provides a convenient and efficient way to synthesize amides. Based on this method, trichlorinated organic compounds were converted into amides in the presence of an amine under aerobic conditions at room temperature in a one-pot procedure. Various trichlorinated organic compounds and an amine source, such as primary, secondary, and cyclic amines, have been evaluated for this transformation, providing the expected products in moderate to excellent yields. Notably, product formation depended on the reaction atmosphere where the amide was obtained under aerobic conditions while partially dechlorinated products were obtained under anaerobic conditions. As this protocol is free from hazardous reagents, extra additives, noble metals, and dangerous gas, the present method provides a novel and efficient approach for amide synthesis under mild and easily controlled conditions.
Method for preparing coupling arene from aryl halide by ionizing, discharging and coupling
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Paragraph 0029-0043; 0059-0063, (2017/09/26)
The invention discloses a method for preparing coupling arene from aryl halide by ionizing, discharging and coupling. The method comprises the following steps: placing a magnetic stirrer into a three-necked flask and adding aryl halide occupying 1/2 flask, thereby finishing the assembling of an ionizing reaction device; placing the ionizing reaction device into an oil bath pan, introducing inert gas into a reaction system, removing air from the reaction system, starting stirring and heating in the oil bath pan to make aryl halide flow back, and meanwhile, introducing water into a ball-shaped condensation pipe for cooling; starting a high-voltage power generator, and introducing powerful arc generated into the three-necked flask through a metal electrode, thereby ionizing and decomposing aryl halide steam and generating a coupling arene compound; stopping ionizing and heating when solids are separated or the backflow of aryl halide is slowed in a round-bottom flask, and then ending the reaction; recrystallizing or performing reduced pressure distillation purification on the coupling arene product in the flask, thereby acquiring the coupling arene product. The method disclosed by the invention has the advantages of low cost, high efficiency, environmental protection, and the like.
Chromium-carbyne complexes: Intermediates for organic synthesis
Bejot, Romain,He, Anyu,Falck, John R.,Mioskowski, Charles
, p. 1719 - 1722 (2008/02/13)
(Chemical Equation Presented) On the same route: Chromium-carbyne complexes are readily prepared by treatment of 1,1,1-trichloromethyl reagents with chromium(II) chloride. They serve as intermediates in the selective formation of a wide variety of products, such as alkynes, alkenes, β-hydroxy ketones, aldehydes, allylic alcohols, and allenes (see scheme, E = electrophile).
Tandem Pd/C-catalyzed reductive coupling and dehalogenation of benzylic halides
Joshi, Ashutosh V.,Baidossi, Mubeen,Taha, Nimer,Mukhopadhyay, Sudip,Sasson, Yoel
, p. 2715 - 2722 (2007/10/03)
High-yield reductive homocoupling of benzotrichloride and benzal chloride followed by consecutive reductive dechlorination to 1,2-dichlorostilbene and stilbene is effected in the presence of sodium formate as the reducing agent and Pd/C catalysts. Copyright Taylor & Francis, Inc.
Inter- and innermolecular reactions of chloro(phenyl)carbene
Rosenberg, Murray G.,Brinker, Udo H.
, p. 4819 - 4832 (2007/10/03)
Supramolecular photolyses of 3-chloro-3-phenyl-3H-diazirine (8) were performed within cyclodextrin (CyD) hosts to determine whether these toroidal inclusion compounds could alter the reactivity of the ensuing carbene reaction intermediate, chloro(phenyl)carbene (9). Remarkably, no intramolecular products stemming from carbene 9 could be detected. Instead, modified CyDs were formed via so-called innermolecular reactions. Hence, diazirine 8 was photolyzed in various conventional solvents to gauge the intermolecular reactivity of carbene 9. Relevant results were used to rationalize the CyD innermolecular reaction products.
Astonishing alkylation and unusual reduction reactions of anionic titanium(II) isopropoxide complexes: Evidence for SET processes in transition-metal oxidative additions
Eisch, John J.,Gitua, John N.
, p. 3091 - 3096 (2007/10/03)
A mixture of titanium(II) isopropoxide and lithium isopropoxide (1:2), generated in THF by the treatment of titanium(IV) isopropoxide with two equivalents of n-butyllithium, has been shown to be an unexpected alkylating agent as well as an unusual reducing agent for a wide variety of organic substrates. Since titanium(II) isopropoxide, which is free of any lithium isopropoxide, neither causes alkylation of any of the same substrates nor is such a powerful reductant, it is proposed that the lithium isopropoxide activates titanium(II) isopropoxide for such unusual reactions by the formation of the lithium salt coordination complex Li2Ti[OiPr]4. Illustrative of the unprecedented alkylations are the transformations, after hydrolysis, of various substituted benzonitriles to isopropyl-substituted phenyl ketones, of (dichloromethyl)benzene to, principally, 2-methyl-1-phenyl-1-propene and of (trichloromethyl)benzene to isopropyl phenyl ketone. By comparing the reducing actions of Li2Ti[OiPr]4 and Ti[OiPr]2 individually, it has been shown that, generally, the lithium salt is the more powerful reductant for epoxides, benzylic halides and conjugated olefins. From the reactions of Li2Ti[OiPr]4 with the benzonitriles, styrene, the isomeric stilbene oxides and cis-stilbene, cogent evidence is marshaled for the operation of SET processes, sensitive to steric hindrance, in such alkylations and reductions. Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002.
Organometallic chemistry sans organometallic reagents: Modulated electron-transfer reactions of sub valent early transition metal salts
Eisch, John J.,Shi, Xian,Alila, Joseph R.,Thiele, Sven
, p. 1175 - 1187 (2007/10/03)
The potential of low-valent, early transition-metal reagents as selective reductants in organic chemistry has been foreshadowed by intensive research on the ill-defined and heterogeneous subvalent titanium intermediates generated in the McMurry reaction and its numerous variants. As part of a long-term research effort to develop soluble, well-defined transition-metal reductants of modulated and selective activity toward organic substrates, the THF-soluble reductant, titanium dichloride, has been thoroughly examined, as well as the analogous ZrCl2 and HfCl2 reagents, all of which are readily obtainable by the alkylative reduction of the Group 4 tetrachloride by butyllithium in THF. Noteworthy is that such interactions of MCl4, with butyllithium in hydrocarbon media lead, in contrast, to M(III) or M(IV) halide hydrides. Analogous alkylative reductions in THF applied to VCl4, CrCl3, and MoCl5 have yielded reducing agents similar to those obtained from MCl4 but gradated in their reactivity. Such reductants have proved capable of coupling carbonyl derivatives, benzylic halides, acetylenes and certain olefins in a manner consistent with an oxidative addition involving a two-electron transfer (TET). Such a reaction pathway is consistent with the observed stereochemistry for pinacol formation from ketones and for the reductive dimerization of alkynes. In contrast to the reaction of CrCl3 with two equivalents of butyllithium, which leads to a CrCl intermediate, the interaction of CrCl3 in THF with four equivalents of butyllithium at -78°C yields a reagent of the empirical formulation, LiCrH4 · 2 LiCl · 2 THF, as supported by elemental and gasometric analysis of its protolysis. This hydridic reductant cleaves a wide gamut of o carbon-heteroatom bonds (C-X, C-O, C-S and C-N), towards which the CrCl reductant is unreactive. The type of cleavage and/or coupled products resulting from the action of "LiCrH4" on these substrates is best understood as arising from single-electron transfer (SET). In light of the aforementioned findings, the gradated reducing action noted among TiCl2, ZrCl2, HfCl2 and CrCl, as well as the contrasting reducing behavior between CrCl and LiCrH4, there is no doubt that future research with early transition metals will continue to yield novel reductants of modulated and site-selective reactivity. VCH Verlagsgesellschaft mbH,.
