103-54-8Relevant articles and documents
Palladium nanoparticles, stabilized by lignin, as catalyst for cross-coupling reactions in water
Coccia, Francesca,Tonucci, Lucia,D'Alessandro, Nicola,D'Ambrosio, Primiano,Bressan, Mario
, p. 12 - 18 (2013)
Palladium nanoparticles of a definite shape (spherical) and dimension (8-14 and 16-20 nm) were prepared employing two water soluble lignin samples as both reducing and stabilizing agent in definitely green experimental conditions, namely aqueous solution, aerobic conditions, moderate temperature, short times. The above nanoparticles were employed as catalyst for a series of carbon-carbon coupling reactions carried out in water at mild conditions. Heck and Suzuki reactions were performed for several substrates, by changing the nature of halogen, the substituents at the aromatic ring, the bases employed and the temperature. Product yields were satisfactory and selectivities very good. Other two cross-coupling reactions, namely Sonogashira and Stille, were also tested: iodine derivatives showed always the best reactivity, while chlorine derivatives did not react.
Benzoquinone Cocatalyst Contributions to DAF/Pd(OAc)2-Catalyzed Aerobic Allylic Acetoxylation in the Absence and Presence of a Co(salophen) Cocatalyst
Kozack, Caitlin V.,Tereniak, Stephen J.,Jaworski, Jonathan N.,Li, Bao,Bruns, David L.,Knapp, Spring M. M.,Landis, Clark R.,Stahl, Shannon S.
, p. 6363 - 6370 (2021)
Palladium(II)-catalyzed allylic acetoxylation has been the focus of extensive development and investigation. Methods that use molecular oxygen (O2) as the terminal oxidant typically benefit from the use of benzoquinone (BQ) and a transition-metal (TM) cocatalyst, such as Co(salophen), to support oxidation of Pd0 during catalytic turnover. We previously showed that Pd(OAc)2 and 4,5-diazafluoren-9-one (DAF) as an ancillary ligand catalyze allylic oxidation with O2 in the absence of cocatalysts. Herein, we show that BQ enhances DAF/Pd(OAc)2 catalytic activity, nearly matching the performance of reactions that include both BQ and Co(salophen). These observations are complemented by mechanistic studies of DAF/Pd(OAc)2 catalyst systems under three different oxidation conditions: (1) O2 alone, (2) O2 with cocatalytic BQ, and (3) O2 with cocatalytic BQ and Co(salophen). The beneficial effect of BQ in the absence of Co(salophen) is traced to the synergistic roles of O2 and BQ, both of which are capable of oxidizing Pd0 to PdII. The reaction of O2 generates H2O2 as a byproduct, which can oxidize hydroquinone to quinone in the presence of PdII. NMR spectroscopic studies, however, show that hydroquinone is the predominant redox state of the quinone cocatalyst in the absence of Co(salophen), while inclusion of Co(salophen) maintains oxidized quinone throughout the reaction, resulting in better reaction performance.
Development of a mild and efficient protocol for the protection and O-alkylation of allyl alcohols
Selvakumar, Kodirajan,Prasath Lingam, Kandapalam Arun,Luxmi Varma, Rama Varma
, p. 36538 - 36543 (2014)
An efficient, pyridine-free protocol has been developed for the protection of the 3°-allyl alcohol of oxindole using a mild base, such as potassium carbonate, under microwave irradiation conditions. The methodology has been tested with a variety of substrates and protecting group reagents, which provides a clean and good yield of the desired products within a short reaction time. the Partner Organisations 2014.
Novel access to carbonyl and acetylated compounds: The role of the tetra-: N -butylammonium bromide/sodium nitrite catalyst
Sheykhan, Mehdi,Moafi, Hadi Fallah,Abbasnia, Masoumeh
, p. 51347 - 51355 (2016)
A novel aerobic oxidation of alcohols without the use of any oxidants was developed. An equimolar catalytic mixture of tetra-n-butylammonium bromide and sodium nitrite catalyzes the aerobic selective oxidation of benzylic alcohols under oxidant-free, base-free and metal-free conditions. The mild reaction conditions allow oxidation of a wide range of benzylic alcohols, chemo-selectively to their carbonyl compounds (68-93% isolated yields). More importantly, high selectivity among different kinds of alcohols (aromatic vs. aliphatic alcohols, primary vs. secondary alcohols as well as alcohols having neutral rings vs. electron-deficient rings) is available by this approach. The method surprisingly switched over to be an efficient acetylation approach in the case of aliphatic alcohols without the use of any transition metal, phosphorous or other toxic reagents or any need for using toxic acyl halides, sulfonyl halides, anhydrides, etc. by the use of only acetic acid as a reagent.
Bismuth (III) nitrate supported onto silica gel, a new catalyst for acetylation of alcohols and phenols under microwave irradiation
Asadolah, Karim,Heravi, Majid M.
, p. 2335 - 2339 (2004)
Bismuth (III) nitrate supported onto silica gel is found to be efficient catalyst for acetylation of alcohols, phenols and naphthals in the presence of acetic anhydride under microwave irradiation in solventless system.
[BF4]: Silver-free and acid-free catalysts for water-inclusive gold-mediated organic transformations
Gomez-Suarez, Adrian,Oonishi, Yoshihiro,Meiries, Sebastien,Nolan, Steven P.
, p. 1106 - 1111 (2013)
The synthesis of a series of digold hydroxide complexes is reported. These diaurated species, of the formula [{Au(NHC)}2(μ-OH)][BF 4] (where NHC = IPrCl, IPr, IPent), were easily prepared via the cationic species [Au(NHC)(NCCH3)][BF4] in aqueous media. The catalytic activity of these novel complexes was tested and compared to that of the previously reported IPr and SIPr derivatives. These digold hydroxide species are highly active in water-inclusive organic transformations, such as the alkyne and nitrile hydration reactions, and the Meyer-Schuster rearrangement. One salient feature of these systems is the lack of any additive to induce catalytic activity.
Manganese-mediated acetylation of alcohols, phenols, thiols, and amines utilizing acetic anhydride
Jain, Isha,Sharma, Ramandeep,Malik, Payal
, p. 2952 - 2960 (2019)
Manganese(II) chloride-catalyzed acetylation of alcohols, phenols thiols and amines with acetic anhydride is reported. This method is environment-friendly and economically viable as it involves inexpensive, relatively benign catalyst, mild reaction condition, and simple workup. Acetylation is performed under the solvent-free condition at ambient temperature and acetylated products obtained in good to excellent yields. Primary, secondary heterocyclic amines, and phenols with various functional groups are smoothly acetylated in good yields. This method exhibits exquisite chemoselectivity, the amino group is preferentially acetylated in the presence of a hydroxyl/thiol group.
Diastereoselective carbonyl allylation with simple olefins enabled by palladium complex-catalyzed C-H oxidative borylation
Tao, Zhong-Lin,Li, Xing-Han,Han, Zhi-Yong,Gong, Liu-Zhu
, p. 4054 - 4057 (2015)
A highly diastereoselective Pd-catalyzed carbonyl allylation of aldehydes and isatins directly using simple acyclic olefins as allylating reagents is described. This transformation is actually a sequential process consisting of a Pd-catalyzed oxidative allylic C-H borylation and an allylboration of carbonyls accelerated by phosphoric acid, wherein a wide scope of olefins could be tolerated. The oxidant is revealed to play a key role in the successful realization of the allylic C-H activation-based allylation.
A Sulfoxide-Promoted, Catalytic Method for the Regioselective Synthesis of Allylic Acetates from Monosubstituted Olefins via C-H Oxidation
Chen, Mark S.,White, M. Christina
, p. 1346 - 1347 (2004)
Sulfoxide ligation to Pd(II) salts is shown to selectively promote C-H oxidation versus Wacker oxidation chemistry and to control the regioselectivity in the C-H oxidation products. A catalytic method for the direct C-H oxidation of monosubstituted olefins to linear (E)-allylic acetates in high regio- and stereoselectivities and preparatively useful yields is described. The method using benzoquinone as the stoichiometric oxidant and 10 mol % of Pd(OAc)2 or Pd(O2CCF3)2 as the catalyst in a DMSO/AcOH (1:1) solution was found to be compatible with a wide range of functionality (e.g., amides, carbamates, esters, and ethers, see Table 2). Addition of DMSO was found to be critical for promoting the C-H oxidation pathway, with AcOH alone or in combination with a diverse range of dielectric media, leading to mixtures favoring Wacker-type oxidation products (Tables 1, S3). To explore the role of DMSO as a ligand, the bis-sulfoxide Pd(OAc)2 complex 1 was formed and found to be an effective C-H oxidation catalyst in the absence of DMSO (eqs 2, 3). Moreover, catalyst 1 effects a reversal of regioselectivity, favoring the formation of branched allylic acetates. Copyright
-
Carroll
, (1941)
-
Pd(0)-catalyzed 1,1-diarylation of ethylene and allylic carbonates
Saini, Vaneet,Liao, Longyan,Wang, Qiaofeng,Jana, Ranjan,Sigman, Matthew S.
, p. 5008 - 5011 (2013)
An efficient protocol for the one-step synthesis of biologically relevant 1,1-diarylalkanes has been described. This reaction introduces two different aryl groups across the terminal end of simple feedstock alkenes such as ethylene and allylic carbonates.
Heiba et al.
, p. 2706 (1968)
Facile One-Pot Immobilization of a Novel Esterase and Its Application in Cinnamyl Acetate Synthesis
Dong, Fengying,Lin, Lin,Wei, Wei,Wei, Dongzhi
, p. 2517 - 2528 (2020)
Abstract: Cinnamyl acetate has a wide application in food industries. This work focuses on cinnamyl acetate synthesis with a novel esterase. estGUZ753, an esterase gene from Geobacillus uzenensis DSMZ 13551, was first cloned and expressed in Pichia pastoris KM71. The optimal activity of EstGUZ753 towards p-NP caprylate was at pH 8.0 and 70?°C, and the half-life at 70?°C was 28?h. Furthermore, EstGUZ753 showed marked tolerance in methanol. The activity of EstGUZ753 increased up to 1.16-fold in 90% methanol after 72?h, and the half-life in it was 336?h. The crude fermentation broth of EstGUZ753 was immobilized directly onto the epoxy resin (Lx-105s), and the immobilized EstGUZ753 exhibited a 99% conversion for cinnamyl acetate synthesis at a high cinnamyl alcohol concentration in 6?h (cinnamyl alcohol: 1.0?M, enzyme dosage: 3%). These characteristics of EstGUZ753 indicated its great potential for organic synthesis. Graphic Abstract: A novel esterase gene from Geobacillus uzenensis DSMZ 13551 was first cloned and expressed in Pichia pastoris KM71. Esterase EstGUZ753 showed marked thermostability at high temperature and tolerance in methanol. Furthermore, the crude fermentation broth of EstGUZ753 was immobilized directly onto the epoxy resin, and immobilized EstGUZ753 exhibited a 99% conversion for cinnamyl acetate synthesis.[Figure not available: see fulltext.]
Synthesis of dinuclear (μ-η3-Allyl)palladium(I) and -platinum(I) complexes supported by chelate-bridging ligands
Yamaguchi, Yu,Yamanishi, Katsunori,Kondo, Mitsuru,Tsukada, Naofumi
, p. 4837 - 4842 (2013)
Dinuclear (μ-η3-allyl)palladium(I) complexes supported by chelate-bridging ligands, (μ-η3-allyl)Pd2(μ-L) (L = N,N′-bis[2-(diphenylphosphino)phenyl]formamidinate, N-(2-diphenylphosphino)phenyl-N′-8-quinolylformamidinate, N,N′-di-8-quinolylformamidinate, N,N′-di-8-quinolylacetamidinate), were synthesized, and some of them were characterized by X-ray crystallography. A dinuclear (μ-η3-allyl)platinum(I) complex, (μ-η3-allyl)Pt2(μ-L), was also synthesized and crystallographically characterized.
Terephthalic acid derived ligand-stabilized palladium nanocomposite catalyst for Heck coupling reaction: without surface-modified heterogeneous catalyst
Jithendra kumara,Krishnamurthy,Kumara swamy,Shashi kumar,Naik, Satish,Krishna,Naik, Nagaraj
, (2017)
A new protocol is reported for the synthesis of a heterogeneous palladium nanocomposite stabilized with a terephthalic acid-derived ligand (N,N-bis(4-hydroxy-3-methoxybenzylidene)terephthalohydrazide). This is a highly insoluble ligand in common organic solvents, except dimethylformamide and dimethylsulfoxide. The resulting palladium nanocomposite acts as an efficient catalyst precursor for Mizoroki–Heck coupling reactions conducted under various reaction conditions. The spectral data suggest that the rate, yield and recycling of the catalyst are more effective for C–C coupling reactions. Copyright
KF-Al2O3 is an efficient solid support reagent for the acetylation of amines, alcohols, and phenols. Impeding effect of solvent on the reaction rate
Yadav, Veejendra K,Ganesh Babu,Mittal, Manish
, p. 7047 - 7051 (2001)
KF-Al2O3 brings about rapid acetylation of a range of amines, alcohols, and phenols with Ac2O/AcCl. Aliphatic alcohols are acetylated chemoselectively in the presence of phenols. 1° alcohols react several times faster than 2° alcohols. 3° alcohols do not react.
Chemoselective acetylation of alcohols, amines, and thiols without catalyst and solvent
Bandgar,Kasture,Kamble
, p. 2255 - 2259 (2001)
Microwave induced rapid and selective acetylation of alcohols, amines and thiols with acetic anhydride was carried out under non-catalytic and solvent free conditions.
A sustainable one-pot synthesis of cinnamyl acetate in triacetin
Wolfson, Adi,Dlugy, Christina,Karanet, Anna,Tavor, Dorith
, p. 4565 - 4567 (2012)
A sustainable one-pot synthesis of cinnamyl acetate from cinnamaldehyde is demonstrated for the first time using immobilized Baker's yeast and free or immobilized acid as catalysts and triacetin as solvent. Employing the immobilized yeast and Amberlyst-36 allowed full conversion and 91% selectivity for cinnamyl acetate after 96 h at room temperature, and both the catalysts and triacetin were successfully recycled.
Biogenic CuFe2O4 magnetic nanoparticles as a green, reusable and excellent nanocatalyst for acetylation reactions under solvent-free conditions
Chutia, Rituparna,Chetia, Bolin
, p. 15200 - 15206 (2018)
A convenient green method has been developed for the synthesis of biogenic CuFe2O4 magnetic nanoparticles using tea extracts within a very short reaction time. The prepared nanoparticles with an average size of 8.78 nm have been used as an effective catalyst for the acetylation of various alcohols, phenols and amines in good to excellent yields under solvent-free conditions. The catalyst was characterized by XRD, XPS, VSM, SEM and TEM study. A magnetic study of the fresh and recycled catalyst after the fourth cycle was performed by VSM measurement. The main advantages of this protocol are simple biogenic synthesis of the catalyst, a reusable and heterogeneous catalytic system, and short reaction times with excellent yields.
A pronounce approach on the catalytic performance of mesoporous natural silica toward esterification of acetic acid with iso-amyl, benzyl, and cinnamyl alcohols
Abd El-Wahab, Mohamed M. M.,El-Gamal, Nadia O.,Goda, Mohamed N.,Said, Abd El-Aziz A.
, (2021/12/14)
Catalytic esterification of acetic acid with iso-amyl, benzyl, and cinnamyl alcohols in the liquid phase over unmodified natural silica catalyst has been studied. The virgin and calcined catalysts were characterized by thermal analyses (Thermogravimetry (TG) and diffrential thermal analysis (DTA)), X-ray diffraction (XRD), X-ray fluorescence (XRF), Fourier transform infrared (FTIR), scanning electron microscope (SEM), and N2 sorption analyses. The acidity of natural silica catalysts was investigated using isopropyl alcohol dehydration and chemisorption of pyridine and dimethyl pyridine. The results indicated that most of the acidic sites are of Br?nsted type and of intermediate strength. The effect of different parameters such as reaction time, molar ratio, catalyst dosage, and calcination temperature was studied. Natural silica catalyst exhibited excellent catalytic performance with a selectivity of 100% to acetate esters formation. The maximum yields of isoamyl, benzyl, and cinnamyl acetate esters obtained in the batch conditions were 80, 81, and 83%, respectively. Whereas on adopting a simple distillation technique, these yields were successfully improved to higher values of 97, 98, and 90%, respectively. Experimental results manifested that the reaction followed Langmuir–Hinshelwood mechanism. Finally, the catalyst could be completely recycled without loss of its activity after four cycles of the esterification reactions.
