100-49-2Relevant articles and documents
Iron catalysed selective reduction of esters to alcohols
Tamang, Sem Raj,Cozzolino, Anthony F.,Findlater, Michael
, p. 1834 - 1838 (2019)
The reaction of (dppBIAN)FeCl2 with 3 equivalents of n-BuLi affords a catalytically active anionic Fe complex; the nature of the anionic complex was probed using EPR and IR experiments and is proposed to involve a dearomatized, radical, ligand scaffold. This complex is an active catalyst for the hydrosilylation of esters to afford alcohols; loadings as low as 1 mol% were employed.
A visible-light-driven transfer hydrogenation on CdS nanoparticles combined with iridium complexes
Li, Jun,Yang, Jinhui,Wen, Fuyu,Li, Can
, p. 7080 - 7082 (2011)
A visible-light-driven transfer hydrogenation of carbonyl and CC compounds has been developed by coupling CdS nanoparticles with iridium complexes, exhibiting high activities, excellent selectivities and a unique pH-dependent catalytic activity.
Highly selective and efficient hydrogenation of carboxylic acids to alcohols using titania supported Pt catalysts
Manyar, Haresh G.,Paun, Cristina,Pilus, Rashidah,Rooney, David W.,Thompson, Jillian M.,Hardacre, Christopher
, p. 6279 - 6281 (2010)
Selective hydrogenation of carboxylic acids to alcohols and alkanes has been achieved under remarkably mild reaction temperatures and H2 pressures (333 K, 0.5 MPa) using Pt/TiO2 catalyst.
Catalytic hydrogenation products of aromatic and aliphatic dicarboxylic acids
Shinde, Sunil B.,Deshpande, Raj M.
, p. 1137 - 1142 (2019)
Hydrogenation of aromatic dicarboxylic acids gave 100 % selectivity to respective cyclohexane dicarboxylic acid with 5 % Pd/C catalyst. 5 % Ru/C catalyst was observed to give over hydrogenation products at 493 K and at lower temperature (453 K) the selectivity for cyclohexane dicarboxylic acids was increased. Hydrogenation of phthalic acid with Ru-Sn/Al2O3 catalyst was observed to give phthalide instead of 1,2-benzene dimethanol or 2-hydroxy methyl benzoic acid. Ru-Sn/Al2O3 catalyst selectively hydrogenated the carboxylic group of cyclohexane dicarboxylic acids to give cyclohexane dimethanol. Use of proper catalysts and reaction conditions resulted in desired products.
On water and in air: Fast and highly chemoselective transfer hydrogenation of aldehydes with iridium catalysts
Wu, Xiaofeng,Liu, Jianke,Li, Xiaohong,Zanotti-Gerosa, Antonio,Hancock, Fred,Vinci, Daniele,Ruan, Jiwu,Xiao, Jianliang
, p. 6718 - 6722 (2006)
(Chemical Equation Presented) Water as solvent: A fast, selective, and high-yielding transfer hydrogenation of a wide range of aldehydes is achieved using IrIII catalysts containing simple ethylene-diamine (en) ligands (see scheme; Ts = p-toluenesulfonyl, TOF = turnover frequency). This procedure is suitable for aldehydes with a wide range of functional groups.
Iron-catalyzed reduction of carboxylic esters to alcohols
Junge, Kathrin,Wendt, Bianca,Zhou, Shaolin,Beller, Matthias
, p. 2061 - 2065 (2013)
A novel catalytic system formed from Fe(stearate)2/NH 2CH2CH2NH2 and polymethylhydrosiloxane was directly developed for the hydrosilylation of carboxylic acid esters to alcohols. The catalytic method exhibits broad substrate scope, including 20 aliphatic, aromatic, and heterocyclic esters. The corresponding alcohols are obtained in moderate to very good yields. The first iron-catalyzed hydrosilylation of carboxylic acid esters to alcohols is described. A catalytic system formed by Fe(stearate)2/NH 2CH2CH2NH2 and polymethylhydrosiloxane (PMHS) is used for this transformation, which has a broad substrate scope, including 20 aliphatic, aromatic, and heterocyclic esters. The corresponding alcohols are obtained in moderate to very good yields. Copyright
Selective Reductions. 30. Effect of Cation and Solvent on the Reactivity of Saline Borohydrides for Reduction of Carboxylic Esters. Improved Procedures for the Conversion of Esters to Alcohols by Metal Borohydrides
Brown, Herbert C.,Narasimhan, S.,Choi, Yong Moon
, p. 4702 - 4708 (1982)
A comparative study of the relative reactivity of saline borohydrides (Li, Na, Ca) for the reduction of carboxylic esters has been made in selected solvents (ether, tetrahydrofuran, diglyme, 2-propanol, and ethanol) at 25 deg C.In ether solvents the reactivity follows the trend LiBH4 > Ca(BH4)2 > NaBH4.On the other hand, in alcohol solvents the order of reactivity is Ca(BH4)2 > LiBH4 > NaBH4.The reactivities of LiBH4 in ethyl ether and THF, of Ca(BH4)2 in THF and 2-propanol, and of NaBH4 in ethanol proved to be promising for the reduction of esters.However, alcoholsolvents are not useful for reductions at elevated temperatures because the decomposition of the reagents becomes competitive with the reduction.A convenient synthetic procedure has been developed for the rapid conversion of esters to alcohols by using LiBH4 in ethyl ether, LiBH4 in THF, and Ca(BH4)2 in THF and utilizing essentially stoichiometric amounts of the reagents.The procedure involves adding toluene to the reaction mixture and bringing the temperature to 100 deg C while allowing the solvent do distill off.Following completion of the reaction, toluene is readily removed under vacuum and the reaction product hydrolyzed.These reductions were generally complete in 0.5 - 2.0 h, and high yields of alcohols (73-96percent) were isolated.A number of ester derivatives, including compounds containing nitro, halo, cyano, and alkoxy groups, diesters, and lactones were reduced by this procedure.The study demonstrated the high selectivity of these reagents, permitting the rapid reduction of the ester group in the presence of many substituents.However, unsaturated esters undergo simultaneous hydroboration when reduced by this procedure.
Stable and easily handled FeIII catalysts for hydrosilylation of ketones and aldehydes
Zhu, Kailong,Shaver, Michael P.,Thomas, Stephen P.
, p. 2119 - 2123 (2015)
The amine-bis(phenolate) iron(III)-catalysed reduction of ketones and aldehydes to the corresponding secondary and primary alcohols by a consecutive hydrosilylation/hydrolysis process is reported. The amine-bis(phenolate) iron(III) catalyst is easily accessible, stable towards moisture and air and has a broad substrate scope.
Discrete iron complexes for the selective catalytic reduction of aromatic, aliphatic, and α,β-unsaturated aldehydes under water-gas shift conditions
Tlili, Anis,Schranck, Johannes,Neumann, Helfried,Beller, Matthias
, p. 15935 - 15939 (2012)
Iron-catalyzed reductions: Selective iron-catalyzed reduction of aldehydes with hydrogen generated in situ by the water-gas shift reaction is presented (see scheme). The generality and selectivity of this mild procedure are demonstrated by the efficient reduction of various aromatic, aliphatic and α,β-unsaturated aldehydes.
Iron-based catalysts for the hydrogenation of esters to alcohols
Chakraborty, Sumit,Dai, Huiguang,Bhattacharya, Papri,Fairweather, Neil T.,Gibson, Michael S.,Krause, Jeanette A.,Guan, Hairong
, p. 7869 - 7872 (2014)
Hydrogenation of esters is vital to the chemical industry for the production of alcohols, especially fatty alcohols that find broad applications in consumer products. Current technologies for ester hydrogenation rely on either heterogeneous catalysts operating under extreme temperatures and pressures or homogeneous catalysts containing precious metals such as ruthenium and osmium. Here, we report the hydrogenation of esters under relatively mild conditions by employing an iron-based catalyst bearing a PNP-pincer ligand. This catalytic system is also effective for the conversion of coconut oil derived fatty acid methyl esters to detergent alcohols without adding any solvent.
The use of - for the carbonylation of primary, secondary and allylic halides
Davies, Stephen G.,Smallridge, Andrew J.,Ibbotson, Arthur
, p. 195 - 201 (1990)
The tricarbonyl nitrosyl ferrate anion (1) is an efficient carbonylation reagent for the formation of methyl esters from primary and secondary alkyl and benzyl halides.The carbonylation of allyl halides results in the exclusive formation of β,γ-unsaturated esters.Studies of the catalytic use of 1 are also described.
A convenient and general iron-catalyzed hydrosilylation of aldehydes
Shaikh, Nadim S.,Junge, Kathrin,Beller, Matthias
, p. 5429 - 5432 (2007)
A general and highly chemoselective hydrosilylation of aldehydes using iron catalysts is reported. Fe(OAc)2 in the presence of tricyclohexylphosphine as ligand and polymethylhydrosiloxane (PMHS) as an economical hydride source forms an efficient catalyst system for the hydrosilylation of a variety of aldehydes. Aryl, heteroaryl, alkyl and α,β-unsaturated aldehydes are successfully reduced to the corresponding primary alcohols. Broad substrate scope and high tolerance against several functional groups make the process synthetically useful.
Reduction of Some Functional Groups with Titanium(IV) Chloride/Sodium Borohydride
Kano, Shinzo,Tanaka, Yasuyuki,Sugino, Eiichi,Hibino, Sstoshi
, p. 695 - 697 (1980)
-
Rate acceleration in nucleophilic alkylation of carbonyl compounds with a new template containing two metallic centers
Ooi, Takashi,Takahashi, Makoto,Maruoka, Keiji
, p. 835 - 837 (1998)
Two aluminum centers aligned in the same direction capture carbonyl groups in such a way that efficient alkyl transfer becomes possible from aluminum to the carbon atom. This occurs via a favorable cyclic six-membered transition state (a). Carbonyl compounds can now be alkylated with otherwise less reactive alkylmetal species.
Improved Second Generation Iron Pincer Complexes for Effective Ester Hydrogenation
Elangovan, Saravanakumar,Wendt, Bianca,Topf, Christoph,Bachmann, Stephan,Scalone, Michelangelo,Spannenberg, Anke,Jiao, Haijun,Baumann, Wolfgang,Junge, Kathrin,Beller, Matthias
, p. 820 - 825 (2016)
Hydrogenation of esters to alcohols with a well-defined iron iPr2PNP pincer complex has been recently reported by us and other groups. We now introduce a novel and sterically less hindered Et2PNP congener that provides superior catalytic activity in the hydrogenation of various carboxylic acid esters and lactones compared to the known complex. Successful hydrogenation proceeds under relatively mild conditions (60°C) with lower catalyst loadings.
Palladium doping of In2O3 towards a general and selective catalytic hydrogenation of amides to amines and alcohols
Sorribes, Iván,Lemos, Samantha C. S.,Martín, Santiago,Mayoral, Alvaro,Lima, Renata C.,Andrés, Juan
, p. 6965 - 6976 (2019)
Herein, the first general heterogeneous catalytic protocol for the hydrogenation of primary, secondary and tertiary amides to their corresponding amines and alcohols is described. Advantageously, this catalytic protocol works under additive-free conditions and is compatible with the presence of aromatic rings, which are fully retained in the final products. This hydrogenative C-N bond cleavage methodology is catalyzed by a Pd-doped In2O3 catalyst prepared by a microwave hydrothermal-assisted method followed by calcination. This catalyst displays highly dispersed Pd2+ ionic species in the oxide matrix of In2O3 that have appeared to be essential for its high catalytic performance.
Bridged bicyclic 2,3-dioxabicyclo[3.3.1]nonanes as antiplasmodial agents: Synthesis, structure-activity relationships and studies on their biomimetic reaction with Fe(II)
D'Alessandro, Sarah,Alfano, Gloria,Di Cerbo, Luisa,Brogi, Simone,Chemi, Giulia,Relitti, Nicola,Brindisi, Margherita,Lamponi, Stefania,Novellino, Ettore,Campiani, Giuseppe,Gemma, Sandra,Basilico, Nicoletta,Taramelli, Donatella,Baratto, Maria Camilla,Pogni, Rebecca,Butini, Stefania
, (2019)
Despite recent advancements in its control, malaria is still a deadly parasitic disease killing millions of people each year. Progresses in combating the infection have been made by using the so-called artemisinin combination therapies (ACTs). Natural and synthetic peroxides are an important class of antimalarials. Here we describe a new series of peroxides synthesized through a new elaboration of the scaffold of bicyclic-fused/bridged synthetic endoperoxides previously developed by us. These peroxides are produced by a straightforward synthetic protocol and are characterized by submicromolar potency when tested against both chloroquine-sensitive and chloroquine-resistant Plasmodium falciparum strains. To investigate their mode of action, the biomimetic reaction of the representative compound 6w with Fe(II) was studied by EPR and the reaction products were characterized by NMR. Rationalization of the observed structure-activity relationship studies was performed by molecular docking. Taken together, our data robustly support the hypothesized mode of activation of peroxides 6a-cc and led to the definition of the key structural requirements responsible for the antiplasmodial potency. These data will pave the way in future to the rational design of novel optimized antimalarials suitable for in vivo investigation.
Unexpected CNN-to-CC Ligand Rearrangement in Pincer-Ruthenium Precatalysts Leads to a Base-Free Catalyst for Ester Hydrogenation
Le, Linh,Liu, Jiachen,He, Tianyi,Malek, Jack C.,Cervarich, Tia N.,Buttner, John C.,Pham, John,Keith, Jason M.,Chianese, Anthony R.
, (2019)
We report the conversion of a series of CNN-pincer-ruthenium complexes Ru(CNN)HCl(CO) to a CC-chelated form Ru(CC)(PR3)2H(CO) on reaction with sodium tert-butoxide and monodentate phosphines. When the phosphine is triphenylphosphine, cis-phosphine complexes form at room temperature, which convert to the trans isomer at elevated temperatures. When the phosphine is tricyclohexylphosphine, only the trans-phosphine isomer is observed. The CC-chelated complexes are active catalysts for the hydrogenation of esters, without the need for added base. The ligand structure-activity relationship in the series of CC-chelated complexes mirrors that in the precursor CNN-Ru complexes, potentially indicating a common catalytic mechanism. Density functional theory calculations establish a plausible mechanism for the CNN-to-CC rearrangement and demonstrate that this rearrangement is potentially reversible under the conditions of ester hydrogenation catalysis.
Homologation of representative boronic esters using in situ generated (halomethyl)lithiums: A comparative study
Soundararajan, Raman,Li, Guisheng,Brown, Herbert C.
, p. 8957 - 8960 (1994)
A comparative study of the homologation of representative boronic esters with in situ generated LiCH2X (X = Cl; Br; I) is presented wherein the reactivity differences arising out of the steric and electronic effects of the migrating groups, and the nature of the ester groups are determined and discussed.
Selective hydrogenation of aromatic compounds using modified iridium nanoparticles
Jiang, He-Yan,Xu, Jie,Sun, Bin
, (2018)
Till now, Ionic liquid-stabilized metal nanoparticles were investigated as catalytic materials, mostly in the hydrogenation of simple substrates like olefins or arenes. The adjustable hydrogenation products of aromatic compounds, including quinoline and relevant compounds, aromatic nitro compounds, aromatic ketones as well as aromatic aldehydes, are always of special interest, since they provide more choices for additional derivatization. Iridium nanoparticles (Ir NPs) were synthesized by the H2 reduction in imidazolium ionic liquid. TEM indicated that the Ir NPs is worm-like shape with the diameter around 12.2?nm and IR confirmed the modification of phosphine-functionalized ionic liquids (PFILs) to the Ir NPs. With the variation of the modifier, solvent and reaction temperature, substrate like quinoline and relevant compounds, aromatic nitro compounds, aromatic ketones as well as aromatic aldehydes could be hydrogenated by Ir NPs with interesting adjustable catalytic activity and chemoselectivity. Ir NPs modified by PFILs are simple and efficient catalysts in challenging chemoselective hydrogenation of quinoline and relevant compounds, aromatic nitro compounds, aromatic ketones as well as aromatic aldehydes. The activity and chemoselectivity of the Ir NPs could be obviously impacted or adjusted by altering the modifier, solvent and reaction temperature.
Selective hydrogenation of amides using Rh/Mo catalysts
Beamson, Graham,Papworth, Adam J.,Philipps, Charles,Smith, Andrew M.,Whyman, Robin
, p. 93 - 102 (2010)
Rh/Mo catalysts formed in situ from Rh6(CO)16 and Mo(CO)6 are effective for the liquid phase hydrogenation of CyCONH2 to CyCH2NH2 in up to 87% selectivity, without the requirement for ammonia to inhibit secondary amine formation. Use of in situ HP-FTIR spectroscopy has shown that decomposition of metal carbonyl precursors occurs during an extended induction period, with the generation of recyclable, heterogeneous, bimetallic catalysts. Variations in Mo:Rh content have revealed significant synergistic effects on catalysis, with optimum performance at values of ca. 0.6, and substantially reduced selectivities at ≥1. Good amide conversions are noted within the reaction condition regimes 50-100 bar H2 and 130-160 °C. Ex situ characterization of the catalysts, using XRD, XPS and EDX-STEM, has provided evidence for intimately mixed (ca. 2-4 nm) particles that contain metallic Rh and reduced Mo oxides, together with MoO3. Silica-supported Rh/Mo analogues, although active, perform poorly at 150 °C and deactivate during recycle.
Selective hydrogenation of primary amides and cyclic di-peptides under Ru-catalysis
Subaramanian, Murugan,Sivakumar, Ganesan,Babu, Jessin K.,Balaraman, Ekambaram
, p. 12411 - 12414 (2020)
A ruthenium(II)-catalyzed selective hydrogenation of challenging primary amides and cyclic di-peptides to their corresponding primary alcohols and amino alcohols, respectively, is reported. The hydrogenation reaction operates under mild and eco-benign conditions and can be scaled-up.
Rhodium nanoparticles entrapped in boehmite nanofibers: Recyclable catalyst for arene hydrogenation under mild conditions
Park, In Soo,Kwon, Min Serk,Kim, Namdu,Lee, Jae Sung,Kang, Kyung Yeon,Park, Jaiwook
, p. 5667 - 5669 (2005)
A new recyclable rhodium catalyst was synthesized by a simple procedure from readily available reagents, which showed high activities in the hydrogenation of various arenes under 1 atm H2 at room temperature. The Royal Society of Chemistry 2005.
Alkane oxidation with peroxides catalyzed by cage-like copper(II) silsesquioxanes
Vinogradov, Mikhail M.,Kozlov, Yuriy N.,Bilyachenko, Alexey N.,Nesterov, Dmytro S.,Shul'pina, Lidia S.,Zubavichus, Yan V.,Pombeiro, Armando J. L.,Levitsky, Mikhail M.,Yalymov, Alexey I.,Shul'pin, Georgiy B.
, p. 187 - 199 (2015)
Isomeric cage-like tetracopper(II) silsesquioxane complexes [(PhSiO1.5)12(CuO)4(NaO0.5)4] (1a), [(PhSiO1.5)6(CuO)4(NaO0.5)4(PhSiO1.5)6] (1b) and binuclear complex [(PhSiO1.5)10(CuO)2(NaO0.5)2] (2) have been studied by various methods. These compounds can be considered as models of some multinuclear copper-containing enzymes. Compounds 1a and 2 are good pre-catalysts for the alkane oxygenation with hydrogen peroxide in air in an acetonitrile solution. Thus, the 1a-catalyzed reaction with cyclohexane at 60°C gave mainly cyclohexyl hydroperoxide in 17% yield (turnover number, TON, was 190 after 230 min and initial turnover frequency, TOF, was 100 h-1). The alkyl hydroperoxide partly decomposes in the course of the reaction to afford the corresponding ketone and alcohol. The effective activation energy for the cyclohexane oxygenation catalyzed by compounds 1a and 2 is 16 ± 2 and 17 ± 2 kcal mol-1, respectively. Selectivity parameters measured in the oxidation of linear and branched alkanes and the kinetic analysis revealed that the oxidizing species in the reaction is the hydroxyl radical. The analysis of the dependence of the initial reaction rate on the initial concentration of cyclohexane led to a conclusion that hydroxyl radicals attack the cyclohexane molecules in proximity to the copper reaction centers. The oxidations of saturated hydrocarbons with tert-butylhydroperoxide (TBHP) catalyzed by complexes 1a and 2 exhibit unusual selectivity parameters which are due to the steric hindrance created by bulky silsesquioxane ligands surrounding copper reactive centers. Thus, the methylene groups in n-octane have different reactivities: the regioselectivity parameter for the oxidation with TBHP catalyzed by 1a is 1:10.5:8:7. Furthermore, in the oxidation of methylcyclohexane the position 2 relative to the methyl group of this substrate is noticeably less reactive than the corresponding positions 3 and 4. Finally, the oxidation of trans-1,2-dimethylcyclohexane with TBHP catalyzed by complexes 1a and 2 proceeds stereoselectively with the inversion of configuration. The 1a-catalyzed reaction of cyclohexane with H216O2 in an atmosphere of 18O2 gives cyclohexyl hydroperoxide containing up to 50% of 18O. The small amount of cyclohexanone, produced along with cyclohexyl hydroperoxide, is 18O-free and is generated apparently via a mechanism which does not include hydroxyl radicals and incorporation of molecular oxygen from the atmosphere.
-
Smith,Brown
, p. 6135 (1952)
-
Deoxygenative hydroboration of primary, secondary, and tertiary amides: Catalyst-free synthesis of various substituted amines
An, Duk Keun,Jaladi, Ashok Kumar,Kim, Hyun Tae,Yi, Jaeeun
, (2021/11/17)
Transformation of relatively less reactive functional groups under catalyst-free conditions is an interesting aspect and requires a typical protocol. Herein, we report the synthesis of various primary, secondary, and tertiary amines through hydroboration of amides using pinacolborane under catalyst-free and solvent-free conditions. The deoxygenative hydroboration of primary and secondary amides proceeded with excellent conversions. The comparatively less reactive tertiary amides were also converted to the corresponding N,N-diamines in moderate yields under catalyst-free conditions, although alcohols were obtained as a minor product.
MOF-derived hcp-Co nanoparticles encapsulated in ultrathin graphene for carboxylic acids hydrogenation to alcohols
Dong, Mei,Fan, Weibin,Gao, Xiaoqing,Zhu, Shanhui
, p. 201 - 211 (2021/06/03)
Highly efficient conversion of carboxylic acids to valuable alcohols is a great challenge for easily corroded non-noble metal catalysts. Here, a series of few-layer graphene encapsulated metastable hexagonal closed-packed (hcp) Co nanoparticles were fabricated by reductive pyrolysis of metal-organic framework precursor. The sample pyrolyzed at 400 °C (hcp-Co@G400) presented outstanding performance and stability for converting a variety of functional carboxylic acids and its turnover frequency was one magnitude higher than that of conventional facc-centered cubic (fcc) Co catalysts. In situ DRIFTS spectroscopy of model reaction acetic acid hydrogenation and DFT calculation results confirm that carboxylic acid initially undergoes dehydroxylation to RCH2CO* followed by consecutive hydrogenation to RCH2CH2OH through RCH2COH*. Acetic acid prefers to vertically adsorb at hcp-Co (0 0 2) facet with a much lower adsorption energy than parallel adsorption at fcc-Co (1 1 1) surface, which plays a key role in decreasing the activation barrier of the rate-determining step of acetic acid dehydroxylation.
Method for synthesizing primary alcohol in water phase
-
Paragraph 0041-0042, (2021/07/14)
The invention discloses a method for synthesizing primary alcohol in a water phase. The method comprises the following steps: taking aldehyde as a raw material, selecting water as a solvent, and carrying out catalytic hydrogenation reaction on the aldehyde in the presence of a water-soluble catalyst to obtain the primary alcohol, wherein the catalyst is a metal iridium complex [Cp*Ir(2,2'-bpyO)(OH)][Na]. Water is used as the solvent, so that the use of an organic solvent is avoided, and the method is more environment-friendly; the reaction is carried out at relatively low temperature and normal pressure, and the reaction conditions are mild; alkali is not needed in the reaction, so that generation of byproducts is avoided; and the conversion rate of the raw materials is high, and the yield of the obtained product is high. The method not only has academic research value, but also has a certain industrialization prospect.
