- Magnetic covalent hybrid of graphitic carbon nitride and graphene oxide as an efficient catalyst support for immobilization of Pd nanoparticles
-
For the first time a magnetic carbon based hybrid catalyst, Pd@g-C3N4-Fe-GO, is prepared through covalent conjugation of magnetic graphitic carbon nitride and graphene oxide followed by incorporation of Pd nanoparticles. First, the formation of the catalyst was confirmed via XRD, TG, BET, TEM, FTIR, ICP and VSM analyses and then its catalytic activity for promoting Suzuki and Sonogashira coupling reactions under mild reaction condition was investigated. To elucidate whether hybridization of two carbon materials could improve the catalytic activity, the catalytic activity of the catalyst was compared with the control catalysts (Pd@g-C3N4 -GO, Pd@g-C3N4-Fe, Pd@ Fe-GO, Pd@g-C3N4, Pd@GO and the GO/g-C3N4 physical hybrid). Moreover, the role of magnetic nanoparticles in the catalytic performance was confirmed. Notably, the catalytic activities of the catalyst and the control sample prepared via physical hybridization of two carbon materials were compared to confirm the effect of covalent conjugation on the catalytic activity. Moreover, the study of the substituent effect of p-substituted phenyl iodides was considered by Hammett plot, which revealed a beneficial effect of electron-withdrawing side groups for the C–C coupling reaction. Finally, the recyclability of Pd@g-C3N4-Fe-GO as well as leaching of Pd and magnetic nanoparticles was studied.
- Sadjadi, Samahe,Malmir, Masoumeh,Heravi, Majid M.,Ghoreyshi Kahangi, Fatemeh
-
-
Read Online
- Gold(I)-Initiated Cycloisomerization/Diels-Alder/Retro-Diels-Alder Cascade Strategy to Biaryls
-
A unique approach to biaryls was developed on the basis of propargyl vinyl ethers and dienophiles substrates via a gold(I)-initiated cycloisomerization/Diels-Alder/retro-Diels-Alder cascade reaction. The scope and mechanism of the reaction were investigated on the basis of a series of synthetic substrates, control experiments, and DFT calculations.
- Jin, Shengfei,Niu, Yujie,Liu, Chengjun,Zhu, Lifeng,Li, Yangming,Cui, Shanshan,Xiong, Zhiling,Cheng, Maosheng,Lin, Bin,Liu, Yongxiang
-
-
Read Online
- A Garratt-Braverman cyclization route towards the synthesis of phenanthridine derivatives and their DNA-binding studies
-
Garratt-Braverman cyclization has been employed to synthesize a series of dihydroisofuran fused phenanthridine derivatives. The established protocol proposes a simpler synthetic alternative to have access to these therapeutically relevant cytotoxic scaffo
- Mandal, Arundhoti,Bhattacharya, Prabuddha,Das, Amit K.,Basak, Amit
-
-
Read Online
- Synthesis of Pyrrolo[2,1,5- cd]indolizine Rings via Visible-Light-Induced Intermolecular [3+2] Cycloaddition of Indolizines and Alkynes
-
A range of indolizine smoothly underwent visible-light-induced intermolecular [3+2] annulations with internal alkynes to afford pyrrolo[2,1,5-cd]indolizine in good to excellent yields with high regioselectivity. Through this cascade reaction, a series of fluoroactive fused indolizines with a large π-system were conveniently synthesized. The usage of visible light as energy source with air as a stoichiometric oxidant under simple conditions makes this process attractive and practical.
- Zhang, Yu,Yu, Yue,Liang, Bing-Bing,Pei, Yong-Yan,Liu, Xiang,Yao, Hua-Gang,Cao, Hua
-
-
Read Online
- Pd(0) nanoparticles immobilized on multinitrogen functionalized halloysite for promoting Sonogashira reaction: studying the role of the number of surface nitrogens in catalytic performance
-
Halloysite nanoclay, Hal, was amine-functionalized and subsequently reacted with 2,4,6-trichloro-1,3,5-triazine, TCT, and ethylenediamine, EDA, to provide multinitrogen containing functionality on the surface of Hal. The resulting surface-modified Hal, Ha
- Sadjadi, Samahe,Heravi, Majid M.,Masoumi, Baharak,Kazemi, Shaghayegh Sadat
-
-
Read Online
- Visible Light-Induced Cascade Cyclization of 3-Aminoindazoles, Ynals, and Chalcogens: Access to Chalcogen-Containing Pyrimido[1,2- b]-indazoles
-
A direct cascade cyclization of 3-aminoindazoles, ynals, and accessible chalcogens facilitated by visible light has been developed. A series of fluoroactive selenium/tellurium-substituted pyrimido[1,2-b]-indazoles were easily accessed in moderate to good yields with a broad scope. Furthermore, we surveyed the spectral properties of selenide pyrimido[1,2-b]-indazoles prepared by this method.
- Zhou, Jinlei,Li, Wen,Zheng, Huitao,Pei, Yongyan,Liu, Xiang,Cao, Hua
-
-
Read Online
- Copper-Catalyzed Intermolecular Trifluoromethylazidation and Trifluoromethylthiocyanation of Allenes: Efficient Access to CF3-Containing Allyl Azides and Thiocyanates
-
A mild and efficient method for copper-catalyzed trifluoromethylazidation and trifluoromethylthiocyanation of allenes was explored. A series of CF3-containing allyl azides and thiocyanates were obtained with high yields and good stereoselectivi
- Zhu, Na,Wang, Fei,Chen, Pinhong,Ye, Jinxing,Liu, Guosheng
-
-
Read Online
- PdCo bimetallic nanoparticles supported on PPI-grafted graphene as an efficient catalyst for Sonogashira reactions
-
A highly active catalyst based on PdCo alloy nanoparticles supported on polypropylenimine dendrimers, grown on graphene nanosheets, was synthesized and used for carbon-carbon cross-coupling Sonogashira reactions. The prepared catalyst facilitated a facile, efficient and environmentally friendly procedure for the Sonogashira reaction under copper and solvent free conditions using ultrasound irradiation at room temperature. The results showed that the catalyst could be easily recovered and reused several times without significant loss of activity.
- Shaabani, Ahmad,Mahyari, Mojtaba
-
-
Read Online
- On the Enantioselective Rhodium-Catalyzed Enyne Cyclization
-
Several chiral ligands were tested in the enantioselective rhodium-catalyzed enyne cyclization, but none gave results comparable to the BINAP ligand. Among the tested catalyst precursors the soon to be commercially available [(COD)Rh(H2O)2
- Hashmi, A. Stephen K.,Haufe, Patrick,Rivas Nass, Andreas
-
-
Read Online
- One-Pot Regiospecific Synthesis of Indolizines: A Solvent-Free, Metal-Free, Three-Component Reaction of 2-(Pyridin-2-yl)acetates, Ynals, and Alcohols or Thiols
-
A novel approach for the synthesis of indolizines from 2-(pyridin-2-yl)acetates, ynals, and alcohols or thiols has been developed. This MCR (multicomponent reaction) that proceeds under the solvent- and metal-free conditions has provided a straightforward path to construct indolizines. Furthermore, this reaction demonstrates other attractive features such as widely available starting materials, mild conditions, good functional group tolerance, and high efficiency.
- Yang, Daji,Yu, Yue,Wu, Yuanheng,Feng, Huiyi,Li, Xuechen,Cao, Hua
-
-
Read Online
- Halloysite nanoclay decorated with 2-amino pyrimidine functionalized poly glycidyl methacrylate: An efficient support for the immobilization of Pd nanoparticles
-
Taking advantage of the synergistic effects between polymer (P) and halloysite clay (Hal) as well as the capability of heteroatom-containing polymers for anchoring nanoparticles and suppressing their leaching, a novel support composed of Hal and 2-amino p
- Sadjadi, Samahe,Koohestani, Fatemeh,Bahri-Laleh, Naeimeh,Didehban, Khadijeh
-
-
Read Online
- Pd@GO/Fe3O4/PAA/DCA: a novel magnetic heterogeneous catalyst for promoting the Sonogashira cross-coupling reaction
-
A hybrid system involving graphene oxide (GO), magnetic oxide (Fe3O4), acrylamide and dicyandiamide was prepared via amine functionalization of GO/Fe3O4 by means of covalent bonding with acrylamide and subsequent reaction with dicyandiamide to provide a multinitrogen containing polymer on the surface of GO. This hybrid system was utilized as a heterogeneous catalyst support for immobilizing Pd nanoparticles to provide the hybrid, Pd@GO/Fe3O4/PAA/DCA. This nano-Pd composite was characterized using Fourier transform infrared, transmission electron microscopy, scanning electron microscopy, vibrating sample magnetometer, thermogravimetric analysis, X-ray diffraction, and ICP techniques and used for promoting Sonogashira cross-coupling under mild reaction conditions. This heterogeneous and magnetic catalyst was easily separated by external magnet and was reused in a model reaction, efficiently up to six times with slight loss of catalytic activity and Pd leaching, showing the suitability of GO/Fe3O4/PAA/DCA for embedding Pd nanoparticles. To check the effect of the number of surface nitrogens of the polymeric chain on the catalytic performance, the activity of the catalyst was compared with Pd@GO/Fe3O4/PAA; increased number of the surface nitrogens on the chain polymer leads to higher loading of Pd and lower the Pd leaching.
- Daraie, Mansoureh,Heravi, Majid M.,Kazemi, Shaghayegh Sadat
-
-
Read Online
- Flexible Construction of Functionalized-Pyrroles under Palladium or Copper Catalysis in the Presence of BF3 ? Et2O
-
We have developed a flexible approach enabling the access to highly functionalized pyrroles under palladium or copper catalysis in the presence of BF3 ? Et2O. This catalytic methodology utilizes commercially available amines as react
- Guo, Wusheng,Liu, Teng,Liu, Yin,Wei, Kun,Yan, Biwei
-
supporting information
(2022/01/26)
-
- Efficient and chemoselective hydrogenation of aldehydes catalyzed by well-defined PN3-pincer manganese(ii) catalyst precursors: An application in furfural conversion
-
Well-defined and air-stable PN3-pincer manganese(ii) complexes were synthesized and used for the hydrogenation of aldehydes into alcohols under mild conditions using MeOH as a solvent. This protocol is applicable for a wide range of aldehydes containing various functional groups. Importantly, α,β-unsaturated aldehydes, including ynals, are hydrogenated with the CC double bond/CC triple bond intact. Our methodology was demonstrated for the conversion of biomass derived feedstocks such as furfural and 5-formylfurfural to furfuryl alcohol and 5-(hydroxymethyl)furfuryl alcohol respectively.
- Gholap, Sandeep Suryabhan,Dakhil, Abdullah Al,Chakraborty, Priyanka,Li, Huaifeng,Dutta, Indranil,Das, Pradip K.,Huang, Kuo-Wei
-
supporting information
p. 11815 - 11818
(2021/11/30)
-
- BiCl3-Facilitated removal of methoxymethyl-ether/ester derivatives and DFT study of -O-C-O- bond cleavage
-
A simple method for the cleavage of methoxymethyl (MOM)-ether and ester derivatives using bismuth trichloride (BiCl3) is described. The alkyl, alkenyl, alkynyl, benzyl and anthracene MOM ether derivatives, as well as MOM esters of both aliphatic and aromatic carboxylic acids, were deprotected in good yields. To better understand the molecular roles of BiCl3and water for MOM cleavage, two possible binding pathways were investigated using the density functional theory (DFT) method. The theoretical results indicate the differential initial binding site preferences of phenolic and alcoholic MOM substrates to the Bi atom and suggest that water plays a key role in facilitating the cleavage of the MOM group.
- Pacherille, Angela,Tuga, Beza,Hallooman, Dhanashree,Dos Reis, Isaac,Vermette, Mélodie,Issack, Bilkiss B.,Rhyman, Lydia,Ramasami, Ponnadurai,Sunasee, Rajesh
-
supporting information
p. 7109 - 7116
(2021/05/03)
-
- Bi(OTf)3-catalyed One-pot Synthesis of α-Halo-β-amino Ketones and Acyl Aziridines from 3-Aryl Propargyl Alcohols
-
A Bi(OTf)3-catalyed reaction of 3-aryl propargyl alcohols with sulfonamide and halogen source was firstly investigated, which provided a facile route for the synthesis of a large variety of α-halo-β-amino ketones. The key intermediates, β-amino
- Zhang, Qinglin,Duan, Yongbin,Guo, Huifeng,Yang, Hong,Zhai, Jiulong,Li, Tiantian,Wang, Zhihai,Lu, Xiaolei,Wang, Yan,Yin, Yan
-
supporting information
p. 1832 - 1838
(2021/06/09)
-
- One-pot synthesis of 3-substituted-4H-[1,2,3] triazolo[5,1-c][1,4]oxazin-6(7H)-ones from propargyl alcohols, chloroacetyl chloride, and sodium azide
-
An efficient, one-pot synthesis of 3-substituted-4H-[1,2,3]triazolo[5,1-c][1,4]oxazin-6(7H)-ones is developed via sequential esterification, substitution, and 1,3-dipolar cycloaddition processes of various propargyl alcohols, chloroacetyl chloride, and so
- Chen, Jun-Min,Liu, Xiao-Ling,Sheng, Shou-Ri,Wei, Mei-Hong,Zhang, Xiao-Lan
-
p. 482 - 485
(2020/11/30)
-
- Water-Tolerant ortho-Acylation of Phenols
-
A metal-free, water-tolerant, and one-pot process for ortho-acylation of phenols promoted by the iodine source/hydrogen peroxide system has been developed. This transformation undergoes ether formation, iodocyclization, C-C bond cleavage, and oxidative hydrolysis in a one-step manner, which is supported by control experiments.
- Dong, Shuang-Feng,Gao, Zhi-Yuan,He, Yu,Liu, Xu,Loh, Teck-Peng,Tian, Jie-Sheng,Wu, Peng
-
supporting information
p. 6594 - 6598
(2021/09/02)
-
- Organocatalytic Regio- and Enantioselective N-Alkylation of Isoxazol-5-ones
-
A chiral phosphoric acid catalyzed regio- and enantioselective reaction between 1-acylamino-3-arylprop-2-yn-1-ols and isoxazol-5-ones has been developed for the first time. With the established protocol, N-alkylation of isoxazol-5-ones was achieved, affording enantioenriched N,N-acetals in 74–99 % yield with 72–88 % ee.
- Li, Pengfei,Liu, Meiwen,Qian, Chenxiao
-
supporting information
p. 6777 - 6780
(2021/12/31)
-
- Silver Mediated Banert Cascade with Carbon Nucleophiles
-
The Banert cascade of propargylic azides can be promoted by simple silver salts, and the triazafulvene intermediate can be intercepted by carbon nucleophiles. Various indoles (>25 examples, up to 92% yield) and electron-rich heterocycles were effective. T
- Alexander, Juliana R.,Kevorkian, Paul V.,Topczewski, Joseph J.
-
supporting information
p. 3227 - 3230
(2021/05/05)
-
- Efficient Synthesis of Polysubstituted Furans through a Base-Promoted Oxacyclization of (Z)-2-En-4-yn-1-ols
-
An efficient base catalyzed oxacyclization of Z-enynols has been developed under transition metal-free reaction conditions, thus resulting in a variety of new di-, tri-, and tetra-substituted furans. This approach allowed us to obtain 32 new compounds. Furthermore, DFT calculations were realized to depict a relationship between the natural population analysis and experimental results with alkyl or aryl groups for the synthesis of 2-benzylfuran. A one-pot Sonogashira/oxacyclization approach offers a flexible, robust and efficient alternative to base catalyzed cyclization is also carried out.
- Hrizi, Asma,Thiery, Emilie,Romdhani-Younes, Moufida,Jacquemin, Johan,Thibonnet, Jér?me
-
supporting information
p. 3798 - 3806
(2021/06/14)
-
- Catalytic enantioselective addition of alkylzirconium reagents to aliphatic aldehydes
-
A catalytic methodology for the enantioselective addition of alkylzirconium reagents to aliphatic aldehydes is reported here. The versatile and readily accessible chiral Ph-BINMOL ligand, in the presence of Ti(OiPr)4 and a zinc salt, facilitates the reaction, which proceeds under mild conditions and is compatible with functionalized nucleophiles. The alkylzirconium reagents are conveniently generated in situ by hydrozirconation of alkenes with the Schwartz reagent. This work is a continuation of our previous work on aromatic aldehydes.
- Carter, Nicholas,González-Soria, María José,Maciá, Beatriz,Vaccari, Jade
-
-
- Accelerating Chemo- And Regioselective Hydrogenation of Alkynes over Bimetallic Nanoparticles in a Metal-Organic Framework
-
Selective semihydrogenation of alkynes has been a long-term and significant target, yet it remains a great challenge. Herein, bimetallic nanoparticles in a metal-organic framework (MOF), i.e., CuPd&at;ZIF-8 composite, featuring a cubic CuPd core and a porous ZIF-8 shell, have been rationally fabricated for this end. Given the unique physicochemical properties, the Cu nanocubes can not only convert solar energy into heat to accelerate the reaction but also serve as the seed for in situ formation of Pd nanoparticles (NPs) on their external surface to regulate the chemoselectivity of Pd active sites. The additional growth of the MOF shell is helpful to stabilize the CuPd core and offer regioselectivity via the steric hindrance effect. Ammonia borane provides active hydrogen species to significantly boost the hydrogenation and ensure the high selectivity. As a result, the CuPd&at;MOF exhibits high efficiency, featuring a turnover frequency (TOF, 6799 min-1) of 5-105 times higher than that in previous reports, and high chemo- and regioselectivity toward the semihydrogenation of alkynes, in the presence of NH3BH3 as a hydrogen source, under visible-light irradiation at ambient temperature.
- Guan, Qiaoqiao,Jiang, Hai-Long,Li, Luyan,Lu, Junling,Yang, Qihao,Yang, Weijie,Yu, Shu-Hong
-
p. 7753 - 7762
(2020/08/21)
-
- Iron-Catalyzed [2+2+2] Annulation of Aliphatic Bridged 1,n-Enynes with Aldehydes for the Synthesis of Fused Pyrans
-
An iron-catalyzed [2+2+2] annulation of aliphatic bridged 1,n-enynes with aldehydes was developed. Aldehydes play a dual role as the precursors of acyl radicals to trigger the cascade cyclization but also as the radical acceptors to terminate the annulation. This two-in-one strategy overcomes the limitation in [2+2+m] cyclization that requires a rigid benzene skeleton as the essential linker, thus enabling the efficient synthesis of functionalized fused [5.6] and [6.6] pyran skeletons.
- Tian, Tian,Wang, Xin,Lv, Leiyang,Li, Zhiping
-
supporting information
p. 4425 - 4428
(2020/06/05)
-
- Regiodivergent Hydration-Cyclization of Diynones under Gold Catalysis
-
Skipped diynones, efficiently prepared from biomass-derived ethyl lactate, undergo a tandem hydration-oxacyclization reaction under gold(I) catalysis. Reaction conditions have been developed for a switchable process that allows selective access to 4-pyrones or 3(2H)-furanones from the same starting diynones. Further application of this methodology in the total synthesis of polyporapyranone B was demonstrated.
- Mu?oz, Miguel A.,Sanz, Roberto,Solas, Marta,Suárez-Pantiga, Samuel
-
supporting information
p. 7681 - 7687
(2020/10/12)
-
- RET INHIBITORS, PHARMACEUTICAL COMPOSITIONS AND USES THEREOF
-
Provided herein are a RET inhibitor, a pharmaceutical composition thereof and uses thereof. In particular, provided is a compound having Formula (I) or a stereoisomer, a geometric isomer, a tautomer, an N-oxide, a solvate, a metabolite, a pharmaceutically acceptable salt or a prodrug thereof. Provided is a pharmaceutical composition comprising the compound, and uses of the compound and pharmaceutical composition thereof for the preparation of a medicament, in particular for treatment and prevention of RET-related diseases and conditions, including cancer, irritable bowel syndrome, and/or pain associated with irritable bowel syndrome.
- -
-
Paragraph 00407; 00416
(2020/07/06)
-
- RET INHIBITORS, PHARMACEUTICAL COMPOSITIONS AND USES THEREOF
-
Provided herein are a RET inhibitor, a pharmaceutical composition thereof and uses thereof. In particular, provided is a compound having Formula (I) or a stereoisomer, a geometric isomer, a tautomer, an N-oxide, a solvate, a metabolite, a pharmaceutically acceptable salt or a prodrug thereof. Provided is a pharmaceutical composition comprising the compound, and uses of the compound and pharmaceutical composition thereof for the preparation of a medicament, in particular for treatment and prevention of RET-related diseases and conditions, including cancer, irritable bowel syndrome, and/or pain associated with irritable bowel syndrome.
- -
-
Paragraph 00230; 00620
(2020/07/05)
-
- Regioselective Iron-Catalysed Cross-Coupling Reaction of Aryl Propargylic Bromides and Aryl Grignard Reagents
-
An iron-catalysed Kumada-type cross-coupling reaction between aryl substituted propargylic bromides and arylmagnesium reagents has been developed. Propargylic coupling products were the main or only outcome, and propargyl/allene regioselectivity was shown to depend on the electronic nature of the substituents on the triple bond of the substrate and on the arylmagnesium halide. Best selectivities were observed when electron donating substituents were present in either reagent. The process is stereoespecific, occurs with configuration inversion and no carbon-based radicals seem to be involved in the mechanism. (Figure presented.).
- Manjón-Mata, Inés,Quirós, M. Teresa,Bu?uel, Elena,Cárdenas, Diego J.
-
supporting information
p. 146 - 151
(2019/12/11)
-
- Fast heck-cassar-sonogashira (hcs) reactions in green solvents
-
The replacement of toxic solvents with greener alternatives in Heck-Cassar-Sonogashira (HCS) cross-couplings was investigated. The fine-tuning of the HCS protocol allowed to achieve complete conversions and high speed under mild conditions. N-Hydroxyethylpyrrolidone (HEP) gave the best results. Moreover, the methodology was successfully applied to the synthesis of an intermediate of the anticancer drug Erlotinib, demonstrating the versatility of the new green protocol.
- Cabri, W.,Corbisiero, D.,Daka, A.,Fantoni, T.,Ferrazzano, L.,Martelli, G.,Ricci, A.,Tolomelli, A.,Viola, A.
-
supporting information
p. 3969 - 3973
(2020/06/08)
-
- Pyridine: N-oxide promoted hydrosilylation of carbonyl compounds catalyzed by [PSiP]-pincer iron hydrides
-
Five [PSiP]-pincer iron hydrides 1-5, [(2-Ph2PC6H4)2HSiFe(H)(PMe3)2 (1), (2-Ph2PC6H4)2MeSiFe(H)(PMe3)2 (2), (2-Ph2PC6H4)2PhSiFe(H)(PMe3)2 (3), (2-(iPr)2PC6H4)2HSiFe(H)(PMe3) (4), and (2-(iPr)2PC6H4)2MeSiFe(H)(PMe3)2 (5)], were used as catalysts to study the effects of pyridine N-oxide and the electronic properties of [PSiP]-ligands on the catalytic hydrosilylation of carbonyl compounds. It was proved for the first time that this catalytic process could be promoted with pyridine N-oxide as the initiator at 30 °C because the addition of pyridine N-oxide is beneficial for the formation of an unsaturated hydrido iron complex, which is the key intermediate in the catalytic mechanism. Complex 4 as the best catalyst shows excellent catalytic performance. Among the five complexes, complex 3 was new and the molecular structure of complex 3 was determined by single crystal X-ray diffraction. A proposed mechanism was discussed.
- Chang, Guoliang,Fenske, Dieter,Fuhr, Olaf,Li, Xiaoyan,Sun, Hongjian,Xie, Shangqing,Yang, Wenjing,Zhang, Peng
-
p. 9349 - 9354
(2020/09/09)
-
- Direct Access to Allenylphosphine Oxides via a Metal Free Coupling of Propargylic Substrates with P(O)H Compounds
-
A direct and convenient approach for the coupling of propargylic substrates with diphenylphosphine oxide in the presence of Tf2O and 2,6-lutidine has been developed. The method provides a general approach for the construction of attractive allenylphosphoryl skeletons with high atom and step economy under metal free conditions.
- Yang, Chun-Hua,Fan, Huihui,Li, Huimin,Hou, Shenyin,Sun, Xiangkun,Luo, Donghao,Zhang, Yinchao,Yang, Zhantao,Chang, Junbiao
-
supporting information
p. 9438 - 9441
(2019/11/20)
-
- Copper-Catalyzed Perfluoroalkylation of Allyl Phosphates with Stable Perfluoroalkylzinc Reagents
-
A general and practical method for copper-catalyzed cross-coupling of allyl phosphates with stable perfluoroalkylzinc reagents has been developed. The reaction proceeds under mild reaction conditions with high efficiency, good functional group tolerance, and high regio- A nd stereoselectivities and provides general, straightforward, and useful access to allyl-perfluoroalkyl compounds. Preliminary mechanistic studies reveal that the allyl copper intermediate may be involved in the catalytic cycle.
- Liu, Lihua,Bao, Xifei,Xiao, Hua,Li, Junlan,Ye, Feifan,Wang, Chaoqin,Cai, Qinhua,Fan, Shilu
-
p. 423 - 434
(2019/01/08)
-
- Neighboring Carbonyl Group Assisted Hydration of Unsymmetrical Aryl Alkynes Overriding Regular Selectivity
-
A mild and highly regioselective gold-catalyzed hydration of γ-acetoxy aryl alkynes leading to anti-Markovnikov products by the assistance of a neighboring carbonyl group is presented. The reaction procedure operates under room temperature conditions with
- Mendhekar, Kishor L.,Pradhan, Tapas R.,Mallampudi, N. Arjunreddy,Mohapatra, Debendra K.
-
p. 5787 - 5797
(2019/08/21)
-
- Rhodium(i)-catalyzed Pauson-Khand-type reaction using formic acid as a CO surrogate: An alternative approach for indirect CO2 utilization
-
Formic acid is found to be an ideal CO surrogate for the rhodium(i)-catalyzed Pauson-Khand-type (PK-type) reaction of various substituted 1,6-enynes to afford bicyclic cyclopentenones in moderate to good yields. High TON value of up to 263 and good results in the gram-scale experiment were also obtained, demonstrating the efficacy of this methodology. In addition, heterocyclic molecules of pharmaceutical importance were also furnished via inter- or intra-molecular hetero-PK-type reactions, further broadening the application of current strategy. In this protocol, formic acid was utilized as a bridging molecule for the conversion of CO2 to CO, since formic acid is manufactured via catalytic hydrogenation of CO2 and releases CO in the presence of acetic anhydride readily. Therefore, this methodology represents a green and indirect approach for chemical valorization of CO2 in the preparation of value-added compounds.
- Lang, Xian-Dong,You, Fei,He, Xing,Yu, Yi-Chen,He, Liang-Nian
-
supporting information
p. 509 - 514
(2019/02/14)
-
- Atom-Economical Ni-Catalyzed Diborylative Cyclization of Enynes: Preparation of Unsymmetrical Diboronates
-
We report a Ni-catalyzed diborylative cyclization of enynes that affords carbo- and heterocycles containing both alkyl- and alkenylboronates. The reaction is fully atom-economical, shows a broad scope, and employs a powerful and inexpensive catalytic Ni-b
- Cabrera-Lobera, Natalia,Quirós, M. Teresa,Brennessel, William W.,Neidig, Michael L.,Bu?uel, Elena,Cárdenas, Diego J.
-
supporting information
p. 6552 - 6556
(2019/08/20)
-
- Ni-Catalyzed Cyclization of Enynes and Alkynylboronates: Atom-Economical Synthesis of Boryl-1,4-dienes
-
We report a novel atom-economical Ni-catalyzed cyclization reaction of enynes with alkynylboronates. The reaction employs a non-expensive Ni salt, a phosphine-based ligand and easy-handling alkynylboronates as boron–carbon source. The reaction provides co
- Cabrera-Lobera, Natalia,Quirós, M. Teresa,Bu?uel, Elena,Cárdenas, Diego J.
-
supporting information
p. 14512 - 14516
(2019/11/11)
-
- Palladium-catalyzed Sonogashira coupling reactions in γ-valerolactone-based ionic liquids
-
It was demonstrated that the γ-valerolactone-based ionic liquid, tetrabutylphosphonium 4-ethoxyvalerate as a partially bio-based solvent can be utilized as alternative reaction medium for copper- and auxiliary base-free Pd-catalyzed Sonogashira coupling reactions of aryl iodides and functionalized acetylenes under mild conditions. Twenty-two cross-coupling products were isolated with good to excellent yields (72–99%) and purity (>98%). These results represent an example which proves that biomass-derived safer solvents can be utilized efficiently in common, industrially important transformations exhibiting higher chemical and environmental efficiency.
- Orha, László,Tukacs, József M.,Kollár, László,Mika, László T.
-
supporting information
p. 2907 - 2913
(2019/12/14)
-
- Controllable chemoselectivity in the coupling of bromoalkynes with alcohols under visible-light irradiation without additives: Synthesis of propargyl alcohols and α-ketoesters
-
The chemoselectivity of visible-light-induced coupling reactions of bromoalkynes with alcohols can be controlled by simple changes to the reaction atmosphere (N2 or O2). A N2 atmosphere favours propargyl alcohols via a direct C-C coupling process, whereas an O2 atmosphere results in the generation of α-ketoesters through the oxidative CC/C-O coupling pathway.
- Ni, Ke,Meng, Ling-Guo,Ruan, Hongjie,Wang, Lei
-
supporting information
p. 8438 - 8441
(2019/07/22)
-
- Bi(OTf)3 catalyzed synthesis of acyclic β-sulfanyl ketones via a tandem Meyer-Schuster rearrangement/conjugate addition reaction
-
A new strategy to prepare acyclic β-carbonyl thioethers from propargyl alcohols and sulfur nucleophiles is reported. The investigation of the reaction substrates scope indicated that primary 3-aryl propargyl alcohols and thiols underwent the transformation smoothly. The reaction probably proceeded a Bi(OTf)3-catalyzed tandem Meyer-Schuster rearrangement of 3-aryl propargyl alcohol, followed by a thiol Michael conjugate addition of thiols to in situ generated α, β-unsaturated ketones. The method was 100% atom economic, high-yielding, and easy to handle, making it a valuable method for the construction of β-carbonyl sulfides.
- Wang, Yuan,Yin, Yan,Zhang, Qinglin,Pan, Wanyong,Guo, Huifeng,Pei, Keke
-
supporting information
p. 2030 - 2034
(2019/07/03)
-
- Efficient transfer hydrogenation of carbonyl compounds catalyzed by selenophenolato hydrido iron(II) complexes
-
Selenophenolato hydrido iron(II) complexes 1–3 cis-[(H)(SeAr)Fe(PMe3)4] (Ar = C6H5 (1), p-MeOC6H4 (2) and o-MeC6H4 (3)) could catalyze transfer hydrogenation of aldehydes and ketones. Among the three complexes, catalyst 1 exhibited the highest catalytic activity. The catalytic reactions took place under very mild conditions, using isopropanol as solvent and hydrogen source, tBuONa as base under 60–80 °C. This catalytic system has good tolerance for many functional groups, such as halides, C[dbnd]C double bonds, nitro groups and cyano groups at the phenyl ring of the substrates.
- Wang, Yangyang,Du, Zhengyin,Zheng, Tingting,Sun, Hongjian,Li, Xiaoyan
-
-
- Synthesis and catalytic application of [PPP]-pincer iron, nickel and cobalt complexes for the hydrosilylation of aldehydes and ketones
-
A new synthetic strategy for the novel diphosphine-phosphine oxide ligand (1) (Ph2P-(C6H4))2P(O)H was designed. A series of [PPP]-pincer Fe, Ni, and Co complexes were prepared. All of them were formed by chelate-assisted P-H activation. Two metal hydrides [(Ph2P-(C6H4))2P(O)]Fe(H)(PMe3)2 (2) and [(Ph2P-(C6H4))2P(O)]Ni(H)(PMe3) (3) were obtained at room temperature. The combination of ligand 1 with Co(PMe3)4Me or Co(PMe3)4 afforded the same Co(i) complex [(Ph2P-(C6H4))2P(O)]Co(PMe3)2 (4) via P-H bond activation. The catalytic performance of the Fe, Ni, and Co complexes for the hydrosilylation of aldehydes and ketones was explored. At a catalyst loading of 2 mol%, complex 2 displayed the best catalytic activity for the hydrosilylation by using (EtO)3SiH as the hydrogen source under mild conditions. Complexes 2, 3, and 4 were characterized by spectroscopic methods and X-ray diffraction analysis.
- Qi, Xinghao,Zhao, Hua,Sun, Hongjian,Li, Xiaoyan,Fuhr, Olaf,Fenske, Dieter
-
p. 16583 - 16590
(2018/10/23)
-
- Visible-Light-Assisted Cobalt-2-(hydroxyimino)-1-phenylpropan-1-one Complex Catalyzed Pd/Cu-Free Sonogashira–Hagihara Cross-Coupling Reaction
-
An effective and inexpensive strategy for the Co(C9H9NO2)3 catalyzed Sonogashira–Hagihara cross-coupling reaction of aryl bromides containing electron-rich and electron-poor substituents with terminal alkynes wa
- Song, Jin-Yi,Zhou, Xuan,Song, He,Liu, Yang,Zhao, Hong-Yan,Sun, Zhi-Zhong,Chu, Wen-Yi
-
p. 758 - 762
(2018/01/27)
-
- Palladium nanoparticles immobilized on cyclodextrin-decorated halloysite nanotubes: Efficient heterogeneous catalyst for promoting copper- and ligand-free Sonogashira reaction in water–ethanol mixture
-
Combining the excellent features of halloysite nanoclay and cyclodextrin, a novel hybrid system was designed and synthesized based on covalent attachment of tosylated cyclodextrin to thiosemicarbazide-functionalized halloysite nanoclay and used for the im
- Sadjadi, Samahe
-
-
- Palladium nanoparticles immobilized on sepiolite–cyclodextrin nanosponge hybrid: Efficient heterogeneous catalyst for ligand- and copper-free C─C coupling reactions
-
A novel hybrid system composed of sepiolite clay and cyclodextrin nanosponge (CDNS) was prepared via reaction of Cl-functionalized sepiolite with amine-functionalized CDNS. CDNS–sepiolite was then applied for immobilization of Pd(0) nanoparticles. The resulting hybrid system, Pd@CDNS-sepiolite, was characterized using various techniques and successfully used as an efficient and heterogeneous catalyst for ligand- and copper-free Sonogashira and Heck coupling reactions under mild reaction conditions. Recycling experiments confirmed that Pd@CDNS-sepiolite was recyclable and could be used for several consecutive reaction runs with slight Pd leaching and loss of catalytic activity.
- Sadjadi, Samahe,Heravi, Majid M.,Raja, Maryam,Kahangi, Fatemeh Ghoreyshi
-
-
- Gold(III)-Catalyzed Regioselective Oxidation/Cycloisomerization of Diynes: An Approach to Fused Furan Derivatives
-
The first gold(III)-catalyzed regioselective oxidation/cycloisomerization of diynes 1 with pyridine N-oxide as the oxidant was developed, providing a range of synthetically valuable and useful fused furan derivatives 3 in moderate to good yields. Control experiments and the confirmation structure of minor products 5 suggest that this chemistry was a concerted gold(III)-catalyzed oxidation/SN2′-type addition/cyclization process via a β-gold vinyloxypyridinium intermediate and a putative vinyl cation intermediate.
- Li, Jian,Xing, Hong-Wen,Yang, Fang,Chen, Zi-Sheng,Ji, Kegong
-
supporting information
p. 4622 - 4626
(2018/08/07)
-
- Iron-Catalyzed Hydroborylative Cyclization of 1,6-Enynes
-
We report first Fe-catalyzed hydroborylative cyclization reaction. The process provides one C?C and one C?B bond in a single operation and shows a wide scope, allowing the formation of carbo- and heterocycles containing a homoallylic boryl unit that can b
- Cabrera-Lobera, Natalia,Rodríguez-Salamanca, Patricia,Nieto-Carmona, Juan C.,Bu?uel, Elena,Cárdenas, Diego J.
-
supporting information
p. 784 - 788
(2017/11/29)
-
- Novel oxime-palladacycle supported on clay composite as an efficient heterogeneous catalyst for Sonogashira reaction
-
A novel supported catalyst formed by an oxime-derived palladacycle supported on clay OxPdCy@clay is synthesized and characterized. This palladium composite promotes the Sonogashira reaction of aryl iodides, bromides and chlorides with terminal alkynes in polyethylene glycol200 at 85 or 130 °C using 0.05–0.1 mol% of palladium loading under copper and phosphine free conditions. This supported palladacycle, OxPdCy@clay, showed a superior catalytic activity than dimeric oxime-palladacycles. Mechanistic studies about the heterogeneous or homogeneous nature of the catalyst show that catalyst is working mainly under heterogeneous conditions. This supported palladacycle OxPdCy@clay can be recycled by simple centrifugation and reused for at least nine consecutive runs with small decrease in activity.
- Gholinejad, Mohammad,Dasvarz, Neda,Nájera, Carmen
-
p. 262 - 270
(2018/09/06)
-
- Ferrocenyl bisoxazoline as an efficient non-phosphorus ligand for palladium-catalyzed copper-free Sonogashira reaction in aqueous solution
-
Pd(OAc)2-catalyzed Sonogashira coupling reactions of alkynes and a variety of aryl halides with 1,3-bis(5-ferrocenylisoxazoline-3-yl)benzene as an efficient non-phosphorus ligand under copper-free conditions are presented. The main advantages over previous methodologies include low catalyst loading (0.2 mol% Pd(OAc)2 and 0.4 mol% ferrocenyl bisoxazoline ligand are sufficient for these coupling reactions), less problematic reaction medium (water–dimethylformamide) and more convenient operation (no requirement for nitrogen protection).
- Yu, Shuyan,Wu, Jingxin,He, Xinwei,Shang, Yongjia
-
-
- Hydrotalcite-supported palladium nanoparticles as catalysts for the hydroarylation of carbon-carbon multiple bonds
-
Palladium nanoparticles supported on Mg/Ca hydrotalcites catalyze the hydroarylation reaction of different alkynes and alkenes with aryl iodides under air in MeCN. The reaction of tertiary propargylic alcohols (1) with aryl iodides (2) yields, stereoselectively, γ,γ-diarylallylic alcohols (3) in moderate to high yields and high selectivity. Also, the HT/Pd hydroarylation reaction with aryl iodides was attempted on norbornene and α,β-unsaturated ketones affording, respectively, exo-aryl bicyclo[2.2.1]heptanes and β-aryl ketones in moderate to high yields. All the reactions described benefit from using a heterogeneous catalyst with evident advantages in terms of reaction purification and recyclability of the catalyst.
- Di Nicola,Arcadi,Gallucci,Mucciante,Rossi
-
supporting information
p. 1952 - 1957
(2018/02/09)
-
- Syntheses of hydrido selenophenolato iron(II) complexes and their catalytic application in hydrosilylation of aldehydes and ketones
-
Three novel selenophenolato hydrido iron(II) complexes [cis-(H)(SeAr)Fe(PMe3)4] (4–6) (Ar=C6H5 (4), p-MeOC6H4 (5) and o-MeC6H4 (6)) were prepared through the reaction of Fe(PMe3)4 with selenophenols ArSeH (1–3) via Se–H activation. The iron hydrido complexes 4, 5 and 6 could catalyze the hydrosilylation of aldehydes and ketones. Among them complex 5 is the best catalyst for this process. Furthermore, α,β-unsaturated alcohols could be obtained from the selective reduction reactions of the corresponding α,β-unsaturated carbonyls catalyzed by hydrido iron(II) complex 5. This catalytic system has good tolerance for some common groups but it is easy to reduce the nitro group to an amino group. The experiments indicate that the chemoselectivity for this catalytic system is –CHO>–NO2>–C([dbnd]O)CH3. The crystal structure of 6 was determined by X-ray diffraction.
- Wang, Yangyang,Ren, Shishuai,Zhang, Wenbo,Xue, Benjing,Qi, Xinghao,Sun, Hongjian,Li, Xiaoyan,Fuhr, Olaf,Fenske, Dieter
-
-
- Transfer hydrogenation of aldehydes catalyzed by silyl hydrido iron complexes bearing a [PSiP] pincer ligand
-
The synthesis and characterization of a series of silyl hydrido iron complexes bearing a pincer-type [PSiP] ligand (2-R2PC6H4)2SiH2 (R = Ph (1) and iPr (5)) or (2-Ph2PC6H4)2SiMeH (2) were reported. Preligand 1 reacted with Fe(PMe3)4 to afford complex ((2-Ph2PC6H4)SiH)Fe(H)(PMe3)2 (3) in toluene, which was structurally characterized by X-ray diffraction. ((2-iPr2PC6H4)SiH)Fe(H)(PMe3) (6) could be obtained from the reaction of preligand 5 with Fe(PMe3)4 in toluene. Furthermore, complex ((2-iPr2PC6H4)Si(OMe))Fe(H)(PMe3) (7) was isolated by the reaction of complex 6 with 2 equiv. MeOH in THF. The molecular structure of complex 7 was also determined by single-crystal X-ray analysis. Complexes 3, 4, 6 and 7 showed good to excellent catalytic activity for transfer hydrogenation of aldehydes under mild conditions, using 2-propanol as both solvent and hydrogen donor. α,β-Unsaturated aldehydes could be selectively reduced to corresponding α,β-unsaturated alcohols. The catalytic activity of penta-coordinate complex 6 or 7 is stronger than that of hexa-coordinate complex 3 or 4.
- Zhang, Peng,Li, Xiaoyan,Qi, Xinghao,Sun, Hongjian,Fuhr, Olaf,Fenske, Dieter
-
p. 14092 - 14099
(2018/04/25)
-
- Synthesis of silyl iron hydride: Via Si-H activation and its dual catalytic application in the hydrosilylation of carbonyl compounds and dehydration of benzamides
-
The hydrido silyl iron complex (o-Ph2PC6H4SiMe2)Fe(PMe3)3H (2) was obtained via the activation of the Si-H bond of the bidentate silyl ligand o-Ph2P(C6H4)SiMe2H (1) by Fe(PMe3)4. 2 showed good to excellent catalytic activity in both the reduction of aldehydes/ketones and the dehydration of benzamide. In addition, with complex 2 as a catalyst, α,β-unsaturated carbonyls could be selectively reduced to the corresponding α,β-unsaturated alcohols. The mechanisms of the formation of 2 and the catalytic dehydration process are proposed and partly experimentally verified.
- Ren, Shishuai,Xie, Shangqing,Zheng, Tingting,Wang, Yangyang,Xu, Shilu,Xue, Benjing,Li, Xiaoyan,Sun, Hongjian,Fuhr, Olaf,Fenske, Dieter
-
p. 4352 - 4359
(2018/03/26)
-
- Sonogashira reaction using arylsulfonium salts as cross-coupling partners
-
Triarylsulfonium, alkyl- and fluoroalkyl(diaryl)-sulfonium, and aryl(dialkyl)sulfonium triflates are successfully used as a new family of cross-coupling participants in the Sonogashira reaction as aryldiazonium, diaryliodonium, and tetraphenylphosphonium salts. It was found that terminal alkynes reacted mildly with triarylsulfonium or (2,2,2-trifluoroethyl)diphenylsulfonium triflate at room temperature under Pdand Cu-cocatalysis to give the corresponding arylalkynes in up to >99% yield. This protocol represents the first use of arylsulfonium salts as cross-coupling partners in the Pd/Cu-catalyzed Sonogashira reaction.
- Tian, Ze-Yu,Wang, Shi-Meng,Jia, Su-Jiao,Song, Hai-Xia,Zhang, Cheng-Pan
-
p. 5454 - 5457
(2017/11/06)
-
- Fe(OTf)3-catalyzed tandem Meyer-Schuster rearrangement/intermolecular hydroamination of 3-aryl propargyl alcohols for the synthesis of acyclic β-Aminoketones
-
Fe(OTf)3-catalyzed synthesis of acyclic β-aminoketones from 3-aryl propargyl alcohols and nitrogen nucleophiles were investigated. Results showed that propargyl alcohols without bulky groups α to the hydroxyl group underwent the transformation smoothly. Sulphonamides exhibited the higher reactivity than amides as the nitrogen nucleophiles and the transformation of acyclic β-aminoketones were finished in shorter reaction time and higher yields. Finally, racemic fluoxetine was efficiently accessed with the present reaction as the first step. This novel synthesis of acyclic β-aminoketones probable proceeded a Fe(OTf)3-catalyzed Meyer-Schuster rearrangement of 3-aryl propargyl alcohols, followed by a intermolecular hydroamination between nitrogen nucleophiles and α, β-unsaturated ketones.
- Tao, Ruiheng,Yin, Yan,Duan, Yongbin,Sun, Yuxing,Sun, Yue,Cheng, Fengkai,Pan, Jinpeng,Lu, Cheng,Wang, Yuan
-
p. 1762 - 1768
(2017/03/08)
-