1203-68-5Relevant articles and documents
Pinpoint-fluorinated phenanthrene synthesis based on C-F bond activation of difluoroalkenes Dedicated to Prof. Véronique Gouverneur on the occasion of her receipt of the 2014 ACS Award for Creative Work in Fluorine Chemistry.
Fuchibe, Kohei,Morikawa, Toshiyuki,Ueda, Ryu,Okauchi, Tatsuo,Ichikawa, Junji
, p. 106 - 115 (2015)
Treatment with a cationic palladium(II) catalyst promoted the Friedel-Crafts-type cyclization of 1,1-difluoro-1-alkenes bearing a biphenyl skeleton to afford regioselectively fluorinated (pinpoint-fluorinated) phenanthrenes via C-F bond activation. The obtained pinpoint-fluorinated phenanthrenes were observed to be organized by π-π and C-H?F interactions to exhibit columnar and layer structures in the solid state.
Suzuki-Miyaura and Hiyama reactions catalyzed by orthopalladated triarylphosphite complexes
B?aszczyk, Izabela,Trzeciak, Anna M.
, p. 9502 - 9507 (2010)
Orthometallated, dimeric, and monomeric palladium complexes with triphenylphoshito ligands and square-planar complexes of the type PdCl 2[P(OR)3]2 (where R=Ph, m-MeC6H 4, o-MeC6H4, C6H3-2,4- tBu2) were applied in the Suzuki-Miyaura and the Hiyama reactions leading to the same product, 2-Mebiphenyl. The desired product was obtained in high yield in reactions performed in ethane-1,2-diol with Cs 2CO3 as a base. The optimized procedure was also applied to the synthesis of other biphenyl derivatives, and in most cases the Suzuki-Miyaura procedure led to higher yields of the product.
Cu(OAc)2-catalyzed coupling of aromatic C-H bonds with arylboron reagents
Shang, Ming,Sun, Shang-Zheng,Dai, Hui-Xiong,Yu, Jin-Quan
, p. 5666 - 5669 (2014)
Cu-catalyzed coupling of aryl C-H bonds with arylboron reagents was accomplished using a readily removable directing group, which provides a useful method for the synthesis of biaryl compounds. The distinct transmetalation step in this Cu-catalyzed C-H coupling with aryl borons provides unique evidence for the formation of an aryl cupperate intermediate.
Palladium catalysed cross-coupling of aryl chlorides with arylboronic acids in the presence of a new tetraphosphine ligand
Feuerstein,Doucet,Santelli
, p. 1458 - 1460 (2001)
Cis,cis,cis-1,2,3,4-tetrakis(diphenylphosphinomethyl)cyclo pentane/[PdCl(C3H5)]2 system catalyses the cross-coupling of aryl chlorides with arylboronic acids with high ratios substrate/catalyst. A turnover number of 6800000 has been obtained for the addition of the activated 2-chloro-5-(trifluoromethyl)nitrobenzene to benzeneboronic acid in the presence of this catalyst.
Restricted rotation in (phenylpyrrolidino)fullerene derivatives
Ajamaa, Fettah,Duarte, Teresa M. Figueira,Bourgogne, Cyril,Holler, Michel,Fowler, Patrick W.,Nierengarten, Jean-Francois
, p. 3766 - 3774 (2005)
A complete series of (phenylpyrrolidino)fullerene derivatives has been prepared. A detailed conformational analysis of these compounds has been carried out by variable-temperature 1H NMR experiments and computational studies. In the case of (phenylpyrrolidino)fullerene derivatives without ortho substituents, dynamic phenomena arising from restricted rotation around the phenyl-pyrrolidine bond are observed. In contrast, as soon as one of the ortho positions of the phenyl ring is substituted, the rotational energy barrier is high enough to prevent observation under our experimental conditions (room temperature to 120°C) of any dynamic exchange resulting from rotation of the phenyl substituent on the pyrrolidine ring. Whereas, in principle, two diastereoisomeric conformers can exist for the ortho-substituted (phenylpyrrolidino)fullerenes, only the atropisomers in which the unsubstituted ortho position is located atop the fullerene sphere are obtained. We conclude that the reaction of the ortho-substituted benzaldehyde derivatives with C 60 is diastereoselective, affording only one of the two possible atropisomers. Wiley-VCH Verlag GmbH & Co. KGaA, 2005.
Homoleptic chelating N-heterocyclic carbene complexes of palladium immobilized within the pores of SBA-15/IL (NHC-Pd@SBA-15/IL) as heterogeneous catalyst for Hiyama reaction
Rostamnia, Sadegh,Golchin Hossieni, Habib,Doustkhah, Esmail
, p. 18 - 23 (2015)
In this work, SBA-15 was selected as a support for the homoleptic chelating N-heterocyclic carbene complexes of palladium. Here, Pd2+ ions were coordinated to N-heterocyclic carbene (NHC-Pd) which also contain ionic liquid. Then, this NHC-Pd@SBA-15/IL catalyst (NHC-Pd active part of the catalyst) was successfully applied in the catalysis of Hiyama coupling reaction with lower mol% Pd rather to previously reported literatures. The role of TBAF and Cs2CO3 in the decrease of Pd mol% was crucial. Recyclability test showed a successful reusability for 5 runs. Simultaneous application of TBAF and NaOH did destroy the silica structure of SBA-15 in the first run.
Carbon dot reduced palladium nanoparticles as active catalysts for carbon-carbon bond formation
Dey, Deepa,Bhattacharya, Tamalika,Majumdar, Biju,Mandani, Sonam,Sharma, Bhagwati,Sarma, Tridib K.
, p. 13821 - 13825 (2013)
Carbon dots were used as a reducing agent for the synthesis of Pd nanoparticles coated with ultrathin carbon dot shells of ca. 4 nm. The resulting composite nanoparticles showed high catalytic activity for the Heck and Suzuki coupling reactions.
Bidentate organochalcogen ligands (N, E; E = S/Se) as stabilizers for recyclable palladium nanoparticles and their application in Suzuki–Miyaura coupling reactions
Sharma, Pratibha,Arora, Aayushi,Oswal, Preeti,Rao,Kaushal,Kumar, Sushil,Kumar, Satyendra,Singh,Kumar Singh, Ajai,Kumar, Arun
, p. 120 - 127 (2019)
Chalcogeno-substituted secondary amines L1 and L2 have been synthesized by the reduction of corresponding imines. Ligands L1 and L2 have been characterized using 1H and 13C{1H} NMR spectroscopy. The Schiff base precursors used for the synthesis of L1 has also been characterized using single crystal x-ray diffraction technique. Both the ligands (L1 and L2) have been used as stabilizers for palladium nanoparticles (PdNPs) 1–4 in two different ratios of Pd:L (1:1 and 1:4). The NPs have been characterized by UV–Vis spectroscopy, powder X-ray diffraction, scanning electron microscopy (SEM), SEM-EDX, and transmission electron microscopy (TEM). The chalcogen donor site showed remarkable role in the stabilization of these nanoparticles. The Pd:L ratio in NPs has been noticed to affect the size and shape of particles and also their catalytic behavior. Size of the NPs has been found to be in a range of 2–3 nm (NPs 1); 4–5 nm (NPs 2); 3–4 nm (NPs 3); and 4–6 nm (NPs 4). When explored as catalyst, the low loading of these NPs gave significant conversions for the coupling of various aryl halides with phenylboronic acid (Suzuki–Miyaura coupling) in a short reaction time of 3 h. The highest catalytic activity has been observed for Pd NPs 1 (Pd:L ratio 1:1) due to the uniformity in the dispersion of particles. The distinct advantage associated with these NPs (1–4) is that they retain catalytic activity after the reaction and are recyclable up to three times. Attempts were made to gain mechanistic insights of catalysis and it was found that both homogeneous and heterogeneous catalytic processes contribute to the catalysis.
Suzuki cross-coupling mediated by tetradentate N-heterocyclic carbene (NHC)-palladium complexes in an environmentally benign solvent
Zhao, Yuanhong,Zhou, Yongyun,Ma, Dandan,Liu, Jingping,Li, Liang,Zhang,Zhang, Hongbin
, p. 1643 - 1646 (2003)
A highly effective, easy to handle and environmentally benign process for palladium mediated Suzuki cross-coupling was developed. By utilizing a solid support based NHC-palladium catalyst, cross couplings of aryl bromides with phenylboronic acid were achieved in neat water under air. A high ratio of substrate to catalyst was also realized.
An unsymmetrical Schiff-base derived recyclable Pd-catalyst for Suzuki–Miyaura and Sonogashira reactions in aqueous media
Das, Pankaj,Gogoi, Achinta,Puzari, Amlan
, (2021)
Abstract: A water-soluble palladium (II) complex containing an unsymmetrical Schiff-base ligand was synthesized and applied as catalyst Suzuki–Miyaura and Sonogashira cross-coupling reactions in aqueous media. Notably, moderate to excellent yields of biaryls were obtained in Suzuki reaction with usually less reactive aryl and heteroaryl chlorides under relatively mild condition. Moderate-to-high yields of aryl-alkynes were also obtained in Sonogashira reactions using aryl bromides. Apart from hydrophilic nature, the accomplishment of reactions in water, high recyclability, broad functional group tolerance, etc., are other advantages of the system. Graphic abstract: [Figure not available: see fulltext.]
Nucleophilic aromatic substitution on aromatic aldimines
Flippin, Lee A.,Carter, David S.,Dubree, Nathan J. P.
, p. 3255 - 3258 (1993)
Ortho-methoxy-substituted benzaldimines derived from 3-amino-2,4-dimethylpentane undergo efficient nucleophilic aromatic substitution with typical organolithium reagents. The aldimine products can be hydrolyzed under mild conditions to provide ortho-alkyl or ortho-phenyl benzaldehyde derivatives.
Structure-Modified Germatranes for Pd-Catalyzed Biaryl Synthesis
Song, Hai-Jie,Jiang, Wei-Tao,Zhou, Qiao-Lan,Xu, Meng-Yu,Xiao, Bin
, p. 9287 - 9291 (2018)
Germanium, a member of 14th group that falls between Si and Sn, has remained considerably ignored as a nucleophile for a long time. Compared with other forms of Ge-containing nucleophiles, germatranes are structure-defined, easily accessible, and stabilized nucleophilic fragments, but they fail to meet the need of high reactivity and facile introducing to organics. Herein, we report a modified structure of germatranes, whose cross-coupling reactivity is greatly improved. The structure can be easily constructed from inexpensive industrial GeO2, and corresponding Ge-Cl and Ge-H can also be obtained after facile transformations. Moreover, Ar-Ge can be effectively synthesized either from Grignard reagents or Pd-catalyzed germylation of aryl halides.
Bis(imino)acenaphthene (BIAN)-supported palladium(ii) carbene complexes as effective C-C coupling catalysts and solvent effects in organic and aqueous media
Crawford, Katherine A.,Cowley, Alan H.,Humphrey, Simon M.
, p. 1456 - 1464 (2014)
The synthesis and catalytic properties of two new 1,2-acenaphthenyl N-heterocyclic carbene-supported palladium(ii) catalysts are presented. The acenaphthenyl carbene has been prepared with mesityl or 1,5-diisopropyl N-aryl substituents. Comprehensive catalytic studies for the Suzuki coupling of aryl halides with aryl boronic acids have been conducted. In general, the diisopropyl-functionalised catalyst showed superior selectivity and reactivity. A comparison of the catalytic performances in dichloromethane, toluene and water at low temperatures (30-40 °C) is also presented. Both catalysts were proficient in the homogeneous Suzuki coupling of aryl iodides, bromides and chlorides with boronic acids in dichloromethane. Similar reactions in water led to the formation of insoluble colloidal catalytic species that still exhibited high activity in the Suzuki reaction with aryl chlorides. Reactions performed in toluene showed intermediate results; partial catalyst decomposition led to concomitant homogeneous and heterogeneous catalysis. The heterogeneous palladium precipitates could be easily recovered by filtration and reactivated for subsequent use. Activation energies determined for aryl bromide-based Suzuki reactions were found to be in the range of 159-171 kJ mol-1 in organic solvents and 111-116 kJ mol-1 in water. The corresponding activation energy for the aryl chloride was found to be 322 kJ mol-1 in water. the Partner Organisations 2014.
Ruthenium complex catalyzed direct ortho arylation and alkenylation of aromatic imines with organic halides
Oi, Shuichi,Ogino, Yukako,Fukita, Susumu,Inoue, Yoshio
, p. 1783 - 1785 (2002)
Matrix presented The ortho position of the aromatic ring of imino group substituted aromatic compounds is directly arylated and alkenylated with organic halides in the presence of a catalytic amount of a ruthenium(II)-phosphine complex.
A highly active and recyclable catalyst: Phosphine dendrimer-stabilized nickel nanoparticles for the Suzuki coupling reaction
Wu, Lei,Ling, Jie,Wu, Zong-Quan
, p. 1452 - 1456 (2011)
We report here the first dendritic phosphine-stabilized nickel nanoparticles, which can be prepared from nickel(II) chloride, a third generation phosphine dendrimer and the surfactant tetraoctylammonium bromide (TOABr) by two-phase reduction using sodium borohydride. The resulting nickel nanoparticles are found to be a highly active and recyclable catalyst for Suzuki coupling reactions, especially those extended to aryl chloride substrates, affording the biaryls in moderate to good yields. Copyright
Modular Arene Difunctionalization of Unactivated C-O and C-H Bonds by Sequential Chromium-Catalyzed Transformations
Rong, Zhi,Luo, Meiming,Zeng, Xiaoming
, p. 6869 - 6873 (2019)
Sequential transformations of unactivated C-O and C-H bonds under chromium catalysis are described. The use of a N-benzyl-substituted imino group as an auxiliary combined with chromium(II) chloride as a precatalyst and 2,3-dichlorobutane as an oxidant allows the arene C-O and C-H bonds to sequentially couple to arylmagnesium reagents to incorporate two identical or different aryl groups into the ortho positions of benzaldehydes.
N-Heterocyclic carbene silver(I), palladium(II) and mercury(II) complexes: Synthesis, structural studies and catalytic activity
Liu, Qing-Xiang,Wang, Hong,Zhao, Xiao-Jun,Yao, Zhao-Quan,Wang, Zhi-Qiang,Chen, Ai-Hui,Wang, Xiu-Guang
, p. 5330 - 5348 (2012)
The bis-benzimidazolium salts, 1,2-bis[2-(N-R-benzimidazolemethyl)phenoxy] ethane chloride (L1H2: R = Et, L2H2: R = nBu), 1,3-bis[2-(N-R-benzimidazolemethyl)phenoxy]propane chloride (L3H2: R = nPr, L4H 2: R = nBu) and bis[N-R-benzimidazolemethyl]mesitylene 2X (L5H2: R = nBu, X = I; L6H 2: R = PyCH2, X = Br and L7H2: R = PhCH2, X = Br), as well as their eight NHC silver(i), palladium(ii) and mercury(ii) complexes, [(L1Ag)2Ag2Cl 4] (1), [L1(PdCl2CH3CN)2] (2), [(L2Ag)2AgCl2][AgCl2] (3), [(L3Ag2Cl2)n] (4), [(L 4Ag2Cl2)n] (5), [L 5HgI][HgI4]0.5 (6), [L6Hg][HgBr 4] (7) and [L7Ag][(NO3)0.76Br 0.24] (8) have been prepared and characterized. The complexes 1-8 adopt four different structures: (1) with bis-macrometallocycles connected via a Ag2Cl4 unit for 1 and via a AgCl2 unit for 3, (2) an open structure formed via one ligand and two metal atoms for 2, (3) 1D polymeric chains formed by the monomers of a cage-like cavity via weak Ag...Cl bonds (monomer: L3Ag2Cl2 for 4 and L4Ag2Cl2 for 5) and (4) a macrocyclic structure formed by one ligand and one metal for 6-8. In the crystal packing of these complexes, 1D supramolecular chains, 2D supramolecular layers and 3D supramolecular architectures are formed via intermolecular weak interactions, including π-π interactions, hydrogen bonds, C-H...π contacts and weak Hg...Br bonds. Particularly, the catalytic activity of the NHC palladium(ii) complex 2 in Suzuki-Miyaura cross-coupling reactions was studied.
Regioselective photochemical Diels-Alder reaction on thiophene derivatives
D'Auria, Maurizio
, p. 6567 - 6570 (1995)
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Pd immobilized in mesoporous silica particles as recyclable catalysts for suzuki-miyaura coupling: Cooperative effects exerted by co-immobilized amine functionalities
Dickschat, Arne T.,Surmiak, Sabrina,Studer, Armido
, p. 1523 - 1528 (2013)
A bifunctional heterogeneous palladium catalyst bearing additional basic sites was successfully prepared by sequential Cu-catalyzed 1,3-dipolar alkyne-azide cycloaddition and thermal nitroxide-exchange reaction of surface-bound alkoxyamines. This catalyst shows high activity in the Suzuki-Miyaura cross-coupling. The additional basic functionality acts cooperatively since an analogous heterogeneous Pd catalyst lacking the amine functionality is less active. Such catalysts can be recycled up to ten times without loss of activity. Georg Thieme Verlag Stuttgart. New York.
Phosphine free diamino-diol based palladium catalysts and their application in Suzuki-Miyaura cross-coupling reactions
Mohanty, Sasmita,Suresh,Balakrishna, Maravanji S.,Mague, Joel T.
, p. 2114 - 2121 (2009)
Inexpensive air and moisture stable diamino-diol ligands [(2-OH-C10H6)CH2(μ-NC4H8N)CH2(C10H6-2-OH)] (1) and [(5-tBuC6H3-2-OH)CH2(μ-NC4H8N)CH2(5-tBuC6H3-2-OH)] (2) were synthesized by reacting corresponding alcohols with formaldehyde and piperazine. Treatment of ligands 1 and 2 with Pd(OAc)2 in 1:1 molar ratio afforded neutral palladium complexes [Pd{(OC10H6)CH2(μ-NC4H8N)CH2(C10H6O)}] (3) and [Pd{(5-tBuC6H3-2-O)CH2(μ-NC4H8N)CH2(5-tBuC6H3-2-O)}] (4) in good yield. The palladium complexes 3 and 4 are employed in Suzuki-Miyaura cross-coupling reactions between phenylboronic acid and several aryl chlorides or bromides. They are found to be competent homogeneous catalysts for a variety of substrates to afford the coupled products in good to excellent yields. The crystal structures of compounds 2 and 4 are also reported.
Fe3O4-SAHPG-Pd0 nanoparticles: A ligand-free and low Pd loading quasiheterogeneous catalyst active for mild Suzuki–Miyaura coupling and C-H activation of pyrimidine cores
Azizollahi, Hamid,Eshghi, Hossein,García-López, José-Antonio
, (2020/09/17)
This paper reports a green magnetic quasiheterogeneous efficient palladium catalyst in which Pd0 nanoparticles have been immobilized in self-assembled hyperbranched polyglycidole (SAHPG)-coated magnetic Fe3O4 nanoparticles (Fe3O4-SAHPG-Pd0). This catalyst has been used for effective ligandless Pd catalyzed Suzuki–Miyaura coupling reactions of different aryl halides with substituted boronic acids at room temperature and in aqueous media. Herein, SAHPG is used as support; it also acts as a reducing agent and stabilizer to promote the transformation of PdII to Pd0 nanoparticles. Also, this environmental friendly quasiheterogeneous catalyst is employed for the first time in the synthesis of new pyrimido[4,5-b]indoles via oxidative addition/C-H activation reactions on the pyrimidine rings, which were obtained with higher yield and faster than when Pd(OAc)2 was used as the catalyst. Interestingly, the above-mentioned catalyst could be recovered in a facile manner from the reaction mixture by applying an external magnet device and recycled several times with no significant decrease in the catalytic activity.
Synthesis of N-Heterocyclic Carbine Silver(I) and Palladium(II) Complexes with Acylated Piperazine Linker and Catalytic Activity in Three Types of C—C Coupling Reactions
Liu, Qingxiang,Zhang, Xiantao,Zhao, Zhixiang,Li, Xinying,Zhang, Wei
supporting information, p. 605 - 613 (2021/02/01)
Two bis-imidazolium salts LH2·Cl2 and LH2·(PF6)2 with acylated piperazine linker and two N-heterocyclic carbene (NHC) silver(I) and palladium(II) complexes [L2Ag2](PF6)2 (1) and [L2Pd2Cl4] (2) were prepared. The crystal structures of LH2·Cl2 and 1 were confirmed by X-ray analysis. In 1, one 26-membered macrometallocycle was generated through two silver(I) ions and two bidentate ligands L. The catalytic activity of 2 was investigated in Sonogashira, Heck-Mizoroki and Suzuki-Miyaura reactions. The results displayed that these C—C coupling reactions can be smoothly carried out under the catalysis of 2.