100891-10-9Relevant articles and documents
An efficient palladium catalyzed Mizoroki-Heck cross-coupling in water
Jadhav, Sanjay N.,Rode, Chandrashekhar V.
, p. 5958 - 5970 (2017)
The homogeneous Pd-catalysed Mizoroki-Heck coupling reaction was successfully performed in water in the absence of any additives under aerobic conditions. The various key reaction parameters that affect the yield of the desired cross-coupling product were optimized. The Pd(PPh3)4/Et3N/H2O/98 °C catalyst system was found to be highly active (TOF = 12 to 14 h-1) towards achieving excellent yield of the Mizoroki-Heck coupling products for a wide range of electron-withdrawing as well as electron-donating aryl bromides and chlorides in the shortest reaction time. Pd(PPh3)4 catalyst deactivation during the Mizoroki-Heck coupling reaction was investigated and to evolve a strategy for achieving ten times Pd-metal recyclability without appreciable loss of its activity. Thus, the proposed mechanism provides access to a variety of olefins in aqueous medium, making this protocol eco-friendly.
The ligand and base-free Pd-catalyzed oxidative Heck reaction of arylboronic acids and olefins
Sun, Peng,Zhu, Yan,Yang, Hailong,Yan, Hong,Lu, Linhua,Zhang, Xiang,Mao, Jincheng
, p. 4512 - 4515 (2012)
Highly effective Pd-catalyzed Heck-type oxidative couplings between arylboronic acids and terminal olefins were reported. It is noteworthy that such reactions could be carried out in the absence of the base and the ligand.
Mizoroki–Heck cross-coupling reactions using palladium immobilized on DABCO-functionalized silica
Jadhav, Sanjay,Patil, Seema,Kumbhar, Arjun,Kamble, Santosh,Salunkhe, Rajashri
, p. 507 - 514 (2019)
A heterogeneous palladium catalyst supported on silica modified by DABCO has been prepared by post-synthetic modification of silica gel. This heterogeneous catalytic system exhibits high activity and stability in the Mizoroki–Heck cross-coupling reaction of various aryl halides with olefins. The reaction proceeds efficiently under efficiently under mild mild reaction conditions and high yield, with the formation of E-isomers selectively. Moreover, we successfully established a gram-scale synthesis, and the catalyst was reused for up to ten catalytic cycles.
Pd nanoparticles in the thermoregulated ionic liquid and organic biphasic system: An efficient and recyclable catalyst for heck reaction
Zeng, Yan,Wang, Yanhua,Xu, Yicheng,Song, Ying,Jiang, Jingyang,Jin, Zilin
, p. 200 - 205 (2013)
A thermoregulated ionic liquid and organic biphasic system composed of ionic liquid [CH3(OCH2CH2)16N +Et3][CH3SO3 -] (IL PEG750) with ILPEG750-stabilized Pd nanoparticles and organic solvents, which allows for not only a highly efficient homogeneous catalytic reaction, but also an easy biphasic separation and reuse of catalyst attributed to the thermoregulated phase-transition property of the system, was employed for Heck reaction. The ILPEG750-stabilized Pd nanoparticle catalyst exhibited high efficiency, more importantly, after reaction the Pd nanoparticle catalyst could be separated from products by simple phase separation and recycled for six times without evident loss of activity. Graphical Abstract: A thermoregulated ionic liquid and organic biphasic system containing [CH3(OCH2CH2)16N +Et3][CH3SO 3 - ] (ILPEG750)-stabilized Pd nanoparticles was applied to Heck reaction for the first time. The Pd nanoparticle catalyst exhibited high efficiency and good recyclability.[Figure not available: see fulltext.]
Immobilization of Pd nanoparticles with functional ionic liquid grafted onto cross-linked polymer for solvent-free Heck reaction
Liu, Gang,Hou, Minqiang,Song, Jiyuan,Jiang, Tao,Fan, Honglei,Zhang, Zhaofu,Han, Buxing
, p. 65 - 69 (2010)
1-Aminoethyl-3-vinylimidazolium bromide ([VAIM]Br) grafted on the cross-linked polymer polydivinylbenzene (PDVB) was synthesized. The copolymers were used as a support to immobilize palladium nanoparticles. The catalyst was characterized by Fourier transform infrared spectroscopy (FT-IR), thermogravimetric (TG) analysis, transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). The catalytic performance of the copolymer-supported Pd nanoparticles for the Heck arylation of olefins with different aryl iodides was studied under solvent-free conditions. The results demonstrated that the catalyst was very active and stable under solvent-free conditions, and could be reused after simple separation. The reason for the high activity and stability of the catalyst is discussed.
Palladium-Catalyzed Arylation of Olefins by Triarylphosphines via C-P Bond Cleavage
Lu, Dapeng,Xu, Yu,Liu, Wenjing,Guo, Lijuan,Sun, Xingxia
, p. 116 - 122 (2015)
C-H Arylation of olefins by triarylphosphines via C-P bond cleavage has been achieved with either Pd0 or PdII catalysts. A variety of olefins and triarylphosphines are tolerated, and we inferred that both Pd0 and PdII could function directly without pre-oxidation or pre-reduction.
Photodriven Transfer Hydrogenation of Olefins
Leow, Dasheng,Chen, Ying-Ho,Hung, Tzu-Hang,Su, Ying,Lin, Yi-Zhen
, p. 7347 - 7352 (2014)
An improved practical method for the photodriven diimide reduction of olefins was investigated. This catalyst-free procedure proceeds at ambient temperature, utilizes air as oxidant and a lower hydrazine loading, and produces inert nitrogen gas as the sole byproduct. Several functional groups were tolerated, and in some cases, the reaction was chemoselective. Challenging substrates such as cinnamate ester derivatives and trans-stilbene were reduced in excellent yields. The small amount of UVA rays emitted from a household compact fluorescent light bulb was proposed to enable the cis/trans isomerization of the diimide and to promote the loss of hydrogen from the diimide.
Copper-catalyzed decarboxylative trifluoromethylation of allylic bromodifluoroacetates
Ambler, Brett R.,Altman, Ryan A.
, p. 5578 - 5581 (2013)
The development of new synthetic fluorination reactions has important implications in medicinal, agricultural, and materials chemistries. Given the prevalence and accessibility of alcohols, methods to convert alcohols to trifluoromethanes are desirable. However, this transformation typically requires four-step processes, specialty chemicals, and/or stoichiometric metals to access the trifluoromethyl-containing product. A two-step copper-catalyzed decarboxylative protocol for converting allylic alcohols to trifluoromethanes is reported. Preliminary mechanistic studies distinguish this reaction from previously reported Cu-mediated reactions.
New N-heterocyclic carbene palladium complex/ionic liquid matrix immobilized on silica: Application as recoverable catalyst for the Heck reaction
Karimi, Babak,Enders, Dieter
, p. 1237 - 1240 (2006)
A new concept of simultaneous covalent anchoring of a N-heterocyclic carbene palladium/ionic liquid matrix on the silica surface and the application of the resulting catalyst in the Heck reaction of a variety of different haloarenes is described. The catalyst shows high thermal stability (up to 280 °C) and could be recovered and reused for four reaction cycles, giving a total TON ? 36 600. Furthermore, TEM coupled with EDX analysis indicate the formation of Pd nanoparticles within the immobilized IL layer.
Highly effective recyclable palladium-catalyzed ligand-free heck reactions under aerobic conditions
Sun, Peng,Qu, Xiaoming,Li, Tingyi,Zhu, Yan,Yang, Hailong,Xing, Zeyong,Mao, Jincheng
, p. 150 - 154 (2012)
An effective protocol was developed for the Heck coupling reactions between various aryl halides and olefins. In the presence of 2 mol% of Pd(OAc) 2, the desired products could be obtained in good yields under ligand-free and aerobic conditions. The catalytic system could be easily recycled for five times with high efficiency. Georg Thieme Verlag Stuttgart. New York.
Synthesis and biological evaluation of celastrol derivatives as anti-ovarian cancer stem cell agents
Li, Xiaojing,Ding, Jie,Li, Ning,Liu, Wenxia,Ding,Zheng, Huijuan,Ning, Yanyan,Wang, Hongmin,Liu, Renmin,Ren, Shaoda
, p. 667 - 679 (2019)
Ovarian cancer is associated with a high percentage of recurrence of tumors and resistance to chemotherapy. Cancer stem cells (CSCs) are responsible for cancer progression, tumor recurrence, metastasis, and chemoresistance. Thus, developing CSC-targeting therapy is an urgent need in cancer research and clinical application. In an attempt to achieve potent and selective anti-CSC agents, a series of celastrol derivatives with cinnamamide chains were synthesized and evaluated for their anti-ovarian cancer activities. Most of the compounds exhibited stronger antiproliferative activity than celastrol, and celastrol derivative 7g with a 3,4,5-trimethoxycinnamamide side chain was found to be the most potent antiproliferative agent against ovarian cancer cells with an IC50 value of 0.6 μM. Additionally, compound 7g significantly inhibited the colony formation ability and reduced the number of tumor spheres. Furthermore, compound 7g decreased the percentage of CD44+, CD133+ and ALDH+ cells. Thus, compound 7g is a promising anti-CSC agent and could serve as a candidate for the development of new anti-ovarian cancer drugs.
Thiosemicarbazone Salicylaldiminato-Palladium(II)-Catalyzed Mizoroki-Heck reactions
Xie, Guanlei,Chellan, Prinessa,Mao, Jincheng,Chibale, Kelly,Smith, Gregory S.
, p. 1641 - 1647 (2010)
Four tridentate thiosemicarbazone salicylaldiminato-palladium(II) complexes of the general formula [Pd(saltsc-R)PPh3] [saltsc = salicylaldehyde thiosemicarbazone; R = H (1), 3-tert-butyl (2), 3methoxy (3), 5-chloro (4)], have been evaluated as catalyst precursors for the Mizoroki-Heck coupling reaction between a variety of electron-rich and electron-poor aryl halides and olefins. The palladium complexes (0.1-1 mol% loading) were found to effectively catalyze these reactions with high yields being obtained when aryl iodides and aryl bromides were utilized. The effects of base, catalyst loading, reaction temperature and reaction time on the catalytic activity of the most active complex were also investigated.
Hg(II) and Pd(II) complexes with a new selenoether bridged biscarbene ligand: Efficient mono- and bis-arylation of methyl acrylate with a pincer biscarbene Pd(II) precatalyst
Rishu,Prashanth, Billa,Bawari, Deependra,Mandal, Ushnish,Verma, Aditya,Choudhury, Angshuman Roy,Singh, Sanjay
, p. 6291 - 6302 (2017)
Two equivalents of 1-benzyl-3-bromoethylbenzimidazolium bromide couple with Na2Se to produce the first selenoether bridged bis-benzimidazolium salt (LH2)Br2. The nitrate (LH2)(NO3)2 and tetrafluoroborate (LH2)(BF4)2 salts were also synthesized from (LH2)Br2. The reaction of Hg(OAc)2 with (LH2)Br2 gave the first pseudo pincer carbene mercury complex, [Hg(L-κ2C)][HgBr4] (C1). Different complexes of Pd(ii) with selenoether bridged carbene were obtained using (LH2)Br2 and (LH2)(NO3)2. Syntheses of these complexes were dependent on the counter anion and the temperature. Thus, the pincer type ionic complex [PdBr(L-κ3CSeC)]Br (C2) was isolated at 80 °C and the pseudo pincer type neutral complex cis-[PdBr2(L-κ2C)] (C3) was isolated at room temperature from (LH2)Br2 and Pd(OAc)2 in DMSO. The nitrate precursor (LH2)(NO3)2 on palladation with Pd(OAc)2 afforded [Pd(L-κ4CBzCSeC)]NO3 (C4) showing an unprecedented intramolecular metallation at the ortho position of the benzyl wingtip of the benzimidazole moiety. The ligand salts and metal complexes have been characterized using HRMS, heteronuclear NMR and IR spectroscopy. Single crystal X-ray structures of the ligand salts (LH2)Br2 and (LH2)(BF4)2 and complexes C1-C4 have also been elucidated. Complex C2 showed good activity for C-C coupling in the mono-Heck reaction of methyl acrylate and arylbromides. Interestingly, the less common bis-arylation was also observed with deactivated arylbromides as the result of double-Heck coupling.
Oxidative Functionalization of Cinnamaldehyde Derivatives: Control of Chemoselectivity by Organophotocatalysis and Dual Organocatalysis
Yoshioka, Eito,Inoue, Maika,Nagoshi, Yuka,Kobayashi, Ayumi,Mizobuchi, Rumiko,Kawashima, Akira,Kohtani, Shigeru,Miyabe, Hideto
, p. 8962 - 8970 (2018)
The catalytic and chemoselective oxidation of cinnamaldehyde derivatives having a C=C bond and formyl group was studied by using two organocatalysts. The visible-light-induced catalysis using rhodamine 6G as an organophotocatalyst promoted the methoxyhydr
Phosphine-Functionalized Chitosan Microparticles as Support Materials for Palladium Nanoparticles in Heck Reactions
Biajoli, André F. P.,Fajardo, André R.,Lemos, Thalia S. A.,de Souza, Jaqueline F.
, (2022/01/11)
Herein, we investigated the activation and stabilization of Pd nanoparticles using microparticles of chitosan-functionalized with phosphine moieties. The catalytic activity of the prepared material was assessed in a series of Heck reactions, which demonst
HETEROCYCLIC COMPOUNDS FOR MODULATING NR2F6
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Paragraph 00393; 00397, (2021/09/04)
The present disclosure relates to compounds capable of modulating the activity of NR2F6. The compounds of the disclosure may be used in methods for the prevention and/or the treatment of diseases and disorders associated with modulating NR2F6 activity.
Oxidative esterification of alcohols by a single-side organically decorated Anderson-type chrome-based catalyst
Wang, Jingjing,Jiang, Feng,Tao, Chaofu,Yu, Han,Ruhlmann, Laurent,Wei, Yongge
supporting information, p. 2652 - 2657 (2021/04/21)
The direct esterification of alcohols with non-noble metal-based catalytic systems faces great challenges. Here, we report a new chrome-based catalyst stabilized by a single pentaerythritol decorated Anderson-type polyoxometalate, [N(C4H9)4]3[CrMo6O18(OH)3C{(OCH2)3CH2OH}], which can realize the efficient transformation from alcohols to esters by H2O2oxidation in good yields and high selectivity without extra organic ligands. A variety of alcohols with different functionalities including some natural products and pharmaceutical intermediates are tolerated in this system. The chrome-based catalyst can be recycled several times and still keep the original configuration and catalytic activity. We also propose a reasonable catalytic mechanism and prove the potential for industrial applications.
