1450-63-1Relevant articles and documents
New role of graphene oxide as active hydrogen donor in the recyclable palladium nanoparticles catalyzed ullmann reaction in environmental friendly ionic liquid/supercritical carbon dioxide system
Cheng, Jinsheng,Zhang, Gencheng,Du, Jin,Tang, Longhua,Xu, Jingying,Li, Jinghong
, p. 3485 - 3494 (2011)
An economical and green pathway: graphene oxide (GO)-supported palladium nanoparticles (Pd NPs) catalyzed a reductive Ullmann reaction of aryl chloride towards biaryl with high conversion and selectivity in ionic liquid (IL)-supercritical carbon dioxide (ScCO2). The combination of IL and ScCO2 provides superior advantages in product separation, catalyst recycling and reuse of the reaction media over traditional organic solvents. Further investigations showed that GO, the novel catalyst support bearing abundant carboxylic, hydroxyl, epoxy and aldehyde groups, can replace the traditional active hydrogen donor readily with much enhanced product separation efficiency. The use of IL, e.g. [hmim][Tf2N], led to obvious improved stability of the Pd NPs, which was helpful for catalyst recycling. Carbon dioxide, a naturally abundant, nonflammable, relatively nontoxic, economical and recyclable "greenhouse" gas, was found to significantly promote the selectivity of the graphene oxide-based Pd NP-catalyzed reductive Ullmann reaction of aryl chloride. Investigations showed that the Pd NP catalyst and IL can be recycled for more than 5 runs without obvious loss of conversion, indicating the economical viability of this process.
Barclay,L.R.C.,Chapman,R.A.
, p. 1754 - 1760 (1965)
IN SITU-GENERATED NICKEL(0)-CATALYZED HOMO-COUPLING OF ALKENYL HALIDES WITH ZINC POWDER. A SPECIFIC OUTCOME IN STEREOCHEMISTRY.
Takagi,Mimura,Inokawa
, p. 3517 - 3522 (1984)
The catalytic activity of nickel(0) generated in situ from nickel(II) salt was examined in a dehalogenative coupling of alkenyl halides with zinc powder. The reaction of alkenyl bromides took place provided that potassium iodide was present to assist the reduction of nickel(II) with zinc powder, and also to convert the alkenyl bromides to the corresponding alkenyl iodides. A speculative view concerning the disproportionation step is advanced in an attempt to explain the unique sterochemistry observed.
Maeda et al.
, p. 1018 (1974)
Ni(0)-TRIALKYLPHOSPHINE COMPLEXES. EFFICIENT HOMO-COUPLING CATALYST FOR ARYL, ALKENYL, AND HETEROAROMATIC HALIDES.
Takagi,Hayama,Sasaki
, p. 1887 - 1890 (1984)
Bis(trialkylphosphine)nickel(0) generated in situ from bis(trialkylphosphine)nickel(II) chloride was found to be an effective catalyst for a homo-coupling of aryl, alkenyl, or heteroaromatic halides with zinc powder. The catalytic reaction proceeded very well in NMP or HMPA solvent under mild conditions to afford dehalogenative-coupling products in good yields.
Fujiwara et al.
, p. 6015 (1968)
Heavy atom free 1,1,4,4-tetraphenylbuta-1,3-diene with aggregation induced emission for photodynamic cancer therapy
Wen, Huijuan,Ma, Juan,Chen, Jianjiao,Ke, Zhen,Zou, Dengfeng,Li, Qiaoyun
, p. 9183 - 9187 (2019)
Common organic molecules usually suffer from aggregation caused quenching (ACQ), which is disadvantageous for imaging guided phototherapy. It is of tremendous significance for a photosensitizer to be well soluble and simultaneously remain highly fluorescent in aqueous solution. Heavy atom free 1,1,4,4-tetraphenylbuta-1,3-diene (denoted as TPD) with aggregation induced emission (AIE) was designed and synthesized by the Knoevenagel reaction. 1,2-Distearoyl-sn-glycero-3-phospho-ethanolamine-N-[methoxy(polyethyleneglycol)-2000] (DSPE-PEG-2000) coated TPD nanoparticles (NPs) show high singlet oxygen generation ability with singlet oxygen sensor green (SOSG) as a probe and still remain highly fluorescent in aqueous solution. In vitro cytotoxicity assay demonstrates that these NPs have a half-maximal inhibitory concentration (IC50) as low as 8.2 μg mL-1. Meanwhile, in vivo fluorescence imaging shows that these NPs can passively target the tumor by the enhanced penetration and retention (EPR) effect within 6 h. Furthermore, in vivo phototherapy suggests that TPD NPs are able to inhibit the growth of a tumor after irradiation without side effects on the normal tissues, including heart, liver, spleen, lungs and kidneys, indicating the low dark toxicity, high phototoxicity and excellent bio-compatibility of such NPs.
Beyond Takai's Olefination Reagent: Persistent Dehalogenation Emerges in a Chromium(III)-μ3-Methylidyne Complex
Anwander, Reiner,Langmann, Jan,Maichle-M?ssmer, C?cilia,Scherer, Wolfgang,Trzmiel, Simon,Werner, Daniel
supporting information, p. 20049 - 20054 (2021/08/06)
Reaction of CHI3 with six equivalents of CrCl2 in THF at low temperatures affords [Cr3Cl3(μ2-Cl)3(μ3-CH)(thf)6] as the first isolable high-yield CrIII μ3-methylidyne complex. Substitution of the terminal chlorido ligands via salt metathesis with alkali-metal cyclopentadienides generates isostructural half-sandwich chromium(III)-μ3-methylidynes [CpR3Cr3(μ2-Cl)3(μ3-CH)] (CpR=C5H5, C5Me5, C5H4SiMe3). Side and decomposition products of the Cl/CpR exchange reactions were identified and structurally characterized for [Cr4(μ2-Cl)4(μ2-I)2(μ4-O)(thf)4] and [(η5-C5H4SiMe3)CrCl(μ2-Cl)2Li(thf)2]. The Cl/CpR exchange drastically changed the ambient-temperature effective magnetic moment μeff from 9.30/9.11 μB (solution/solid) to 3.63/4.32 μB (CpR=C5Me5). Reactions of [Cr3Cl3(μ2-Cl)3(μ3-CH)(thf)6] with aldehydes and ketones produce intricate mixtures of species through oxy/methylidyne exchange, which were partially identified as radical recombination products through GC/MS analysis and 1H NMR spectroscopy.
Synthesis of Buta-1,3-dienes through Palladium-Catalyzed Homocoupling of Aromatic Alkenes
Wen, Yanmei,Xie, Jianying,Deng, Chunmei,Wu, Yulian
supporting information, p. 1755 - 1758 (2015/07/20)
A series of buta-1,3-dienes have been directly synthesized via a convenient palladium-catalyzed homodehydrogenation coupling reaction of aromatic alkenes under mild conditions. The homocoupling reaction enables a rapid synthesis of multisubstituted butadiene which shows typical aggregation-induced emission enhancement (AIEE) characteristics because it is practically not emissive in solution but emits blue fluorescence in aggregates.
