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One-Pot Synthesis (one-pot + synthesis)
Kinds of One-Pot Synthesis Selected AbstractsFacile One-Pot Syntheses of Amidines and Enamines from Oximes via Beckmann Rearrangement Using Trifluoromethansulfonic Anhydride.CHEMINFORM, Issue 33 2004Tomofumi Takuwa Abstract For Abstract see ChemInform Abstract in Full Text. [source] One-Pot Syntheses of 6-Mercaptopurines (6MP) from 4,5-Diamino-6-chloro-pyrimidines.CHEMINFORM, Issue 25 2004Sagun Tandel Abstract For Abstract see ChemInform Abstract in Full Text. [source] Benzylamines as Versatile Agents for the One-Pot Synthesis and Highly Ordered Stacking of Anatase NanoplateletsEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 6 2008Georg Garnweitner Abstract The simple reaction of titanium isopropoxide in benzylamine is shown to lead to remarkably complex, highly ordered hybrid structures. These structures consist of anatase nanoplatelets that were stacked in a lamellar fashion with a small organic layer in between. By careful characterization of these structures, we show that indeed solely the benzylamine solvent is present in the organic moiety between the nanocrystals, which thereby provides both shape control and alignment of the inorganic crystals. The solvent also plays a central role during the anatase formation itself; hence, it enacts control on the forming materials on a multitude of levels.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] Structural Characterization and a New One-Pot Synthesis of trans -Chloro(phenyl)bis(triphenylphosphane)nickel(II)EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 9 2003Alexander Zeller Abstract trans -[NiCl(Ph)(PPh3)2], the organometallic precursor for a new class of neutral polymerization catalysts, has been synthesized via a new synthetic route. The previously used alkylaluminum compounds are replaced by zinc dust for the reduction of the nickel(II) salt in the presence of triphenylphosphane forming the intermediate Ni(PPh3)4. In a one-pot reaction, chlorobenzene then adds oxidatively to the intermediate to form the title compound, which was structurally characterized, in high yields. Its geometry is compared to known structures of the higher homologues of group 10. All complexes adopt a distorted square-planar geometry, but the parent structure shows significantly shorter metal-ligand bond lengths than its Pd and Pt congeners, as expected. Density functional theory calculations (B3LYP/6,31G*) on the full structure are in very good agreement with the solid-state structure. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003) [source] One-Pot Synthesis of 3-Aryltetramic AcidsEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 6 2010Aurélie Mallinger Abstract Tetramic acids substituted in the 3-position by various aryl groups were prepared in one-pot from amino esters and methyl arylacetates, by treatment with potassium tert -butoxide. A tandem process, involving the formation of an amide and a condensation reaction, is likely to occur. N -Unsubstituted tetramic acids were obtained from adducts containing a N -(2,4-dimethoxybenzyl) group. [source] One-Pot Synthesis of Fluorinated 1-Benzoyl-3,4-dihydroisoquinolines from [2-(o -Alkynylphenyl)ethyl]amines by a Hydroamination/Oxidation SequenceEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 1 2010René Severin Abstract Fluorinated 1-benzoyl-3,4-dihydroisoquinolines can easily be synthesized by a new one-pot procedure from corresponding fluorinated [2-(o -alkynylphenyl)ethyl]amines in high yields. The one-pot process consists of an initial [Ind2TiMe2]-catalyzed intramolecular alkyne hydroamination and a subsequent Pd-catalyzed oxidation of the benzyl side chain of the resulting hydroamination product. The process tolerates electron-donating and -withdrawing substituents on the benzene ring that is converted into the benzoyl side chain of the products as well as ortho -substitution. [source] A Novel, Highly Efficient, One-Pot Synthesis of 1,4-Dihydroquinoline Derivatives in the Presence of a Pd(OAc)2/DABCO Catalytic SystemEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 29 2009Xiao-Jin Wu Abstract The Pd(OAc)2/DABCO catalytic system was first found to be highly efficient for C,N cross-coupling reactions. With the aid of this transformation, a variety of new 1,4-dihydroquinoline derivatives were synthesized from o -halobenzaldehydes and various ,-enaminones in good to excellent yields. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] A Facile and Efficient One-Pot Synthesis of Substituted Quinolines from ,-Arylamino Ketones Under Vilsmeier ConditionsEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 24 2009Yan Wang Abstract An efficient one-pot synthesis of substituted quinolines from ,-arylamino ketones in the presence of PBr3 in DMF has been developed. This general protocol provides a novel and facile access to substituted quinolines by sequential Vilsmeier,Haack reaction, intramolecular cyclization and aromatization reactions of ,-arylamino ketones. PBr3 plays a dual role in the quinoline synthesis: as a key component of the Vilsmeier reagent (PBr3/DMF) and as a reducing reagent. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] Protonation of Diarylacetylenes in Superacid HSO3F and Their Oxidation in the HSO3F/PbO2 System: One-Pot Synthesis of Polysubstituted NaphthalenesEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 27 2008Aleksander V. Vasilyev Abstract In the superacid HSO3F, diarylacetylenes bearing one electron-withdrawing group (NO2, CN, COMe, CO2Me) in each arene ring form stable ions, protonated at these groups. Oxidation of such diarylacetylenes in the HSO3F/PbO2 system at ,75 to ,50 °C over 2,2.5 h, followed by quenching of the reaction mixture with hydrochloric (or hydrobromic) acid at ,60 to 25 °C, resulted in the formation of (E,E)-1,4-dichloro (or dibromo)-1,2,3,4-tetraarylbuta-1,3-dienes. These butadienes spontaneously undergo electrocyclic transformation into polysubstituted naphthalenes at room temperature. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] Iron,Palladium Association in the Preparation of Indoles and One-Pot Synthesis of Bis(indolyl)methanesEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 32 2007Vincent Terrasson Abstract Indoles were prepared by annulation of the parent alkynylanilines with the use of a new FeCl3,PdCl2 catalytic combination. High yields were obtained by using low loadings of the transition-metal complex (FeCl3,PdCl2: 2 and 1 mol-%, respectively). One-pot accesses to bis(indolyl)methanes and trisubstituted indoles through annulation/Friedel,Crafts alkylation and annulation/1,4-Michael addition sequences, in which FeCl3 acts both as a cooxidant and a Lewis acid are described.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] One-Pot Synthesis of Core-Modified Rubyrin, Octaphyrin, and Dodecaphyrin: Characterization and Nonlinear Optical PropertiesEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 27 2007Rajeev Kumar Abstract Modified 26, rubyrin, 36, octaphyrin, and 54, dodecaphyrin systems have been synthesized in moderately good yields through acid-catalyzed condensations of terthiophene diols and tripyrranes. The product distributions are decided both by the acid catalyst concentration and by the nature of the meso substituents. For example, a new isomer of [26]hexaphyrin(1.1.1.1.0.0) (rubyrin) was obtained with 0.3 equiv. of p -toluenesulfonic acid, when the meso substituent was mesityl in at least one of the precursors. A change of the mesityl substituent for a p -methoxy substituent in terthiophene diol resulted in the formation of a [3,+,3,+,3,+,3] condensation product , [54]dodecaphyrin(1.1.1.1.0.0.1.1.1.1.0.0) , in addition to the expected rubyrin. Furthermore, an increase in the acid concentration to 0.6 equiv. resulted in the formation of a new [36]octaphyrin(1.1.1.1.1.1.0.0), in addition to the rubyrin and dodecaphyrin. A single-crystal X-ray analysis of octaphyrin represents the first example of a planar conformation of an octaphyrin with six meso links. In rubyrin 19, one thiophene ring, opposite to the terthiophene subunit, is inverted, while in octaphyrin 30 one pyrrole ring and two thiophene rings are inverted. The various conformational possibilities tested for the unsubstituted dodecaphyrin 28, at semiempirical level, suggest that the most stable conformation is a figure-eight. The final geometry optimization of figure-eight dodecaphyrin was done at the B3LYP/6-31G* level of DFT. Octaphyrins and dodecaphyrins bind trifluoroacetate anion effectively in their diprotonated forms, the binding constants (K) being 638 M,1 for dodecaphyrin 28, and 415 M,1 for octaphyrin 30. Electrochemical data reveal HOMO destabilization with increasing , electron conjugation, consistently with the large red shifts of the absorption bands. Preliminary studies on the use of these expanded porphyrins as third-order NLO materials were followed by measurements of their two-photon absorption (TPA) cross-sections [,(2)]. The ,(2) values increase upon going from the 26, rubyrins to the 54, dodecaphyrins, confirming our earlier observation that increases in ,-conjugated electrons increase the TPA values.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] One-Pot Synthesis of 3-Substituted Isoquinolin-1-(2H)-ones and Fused Isoquinolin-1-(2H)-ones by SRN1 Reactions in DMSOEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 17 2006Javier F. Guastavino Abstract 3-Substituted isoquinolin-1-(2H)-ones and fused isoquinolin-1-(2H)-ones have been obtained by the photostimulated SRN1 reactions of 2-iodobenzamide with the enolates of aromatic (acetophenone, 1-(benzo[d][1,3]dioxol-5-yl)ethanone, 1- and 2-naphthyl methyl ketones, and 2-, 3-, and 4-acetylpyridine), aliphatic (1-adamantyl methyl ketone), and cyclic ketones (1- and 2-indanone, ,- and ,-tetralone, and 1-benzosuberone) in DMSO. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] A One-Pot Synthesis of Doubly Unsaturated Trifluoromethyl Amines:Easy Access to CF3 -Substituted PiperidinesEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 7 2005Guillaume Magueur Abstract A straightforward route to trifluoromethyl analogs of piperidines is described. These syntheses involve a Barbier-type allylation reaction of trifluoroacetaldimines, followed by N -allylation (one-pot), and ring-closing metathesis. An efficient asymmetric version is also reported (>98,% de). Functionalized heterobicyclic compounds can also be obtained by a Pauson,Khand reaction. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source] New, Regioselective, One-Pot Synthesis of (all- E)-Retinoic Acid and Analogues from Enaminodiester SynthonsEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 12 2003Dominique Cartier Abstract A one-pot synthesis of (all- E)-retinoic acid and related compounds from new enamino diester synthons is described. The enamino diesters was produced nearly quantitatively from methyl propylidene- and isopropylidenemalonate and DMF,DMA. This easy process allowed retinoic acid to be produced in 1 d and appeared advantageous to current industrial syntheses. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003) [source] Hybrid Nanofiber Growth: One-Pot Synthesis of Functional Helicoidal Hybrid Organic,Inorganic Nanofibers with Periodically Organized Mesoporosity (Adv. Funct.ADVANCED FUNCTIONAL MATERIALS, Issue 18 2009Mater. Luminescent nanofibers are grown with controlled alignment of twisted nanochannels, as described by K. Valle and co-workers on page 2896. Tuning of the main synthesis parameters (sol-gel conditions, temperatures, choice of surfactants and inorganic precursors) allows the fine control of morphology, porosity-architecture, and organic chemical functionalization in order to prepare useful functional nanofibers. [source] One-Pot Synthesis of Functional Helicoidal Hybrid Organic,Inorganic Nanofibers with Periodically Organized MesoporosityADVANCED FUNCTIONAL MATERIALS, Issue 18 2009Frédéric Rambaud Abstract The one-pot synthesis and properties of multifunctional hybrid mesoporous organosilica fibers with helical shapes are described. These hybrid mesoporous fibers are prepared without chiral elements and functionalized with a large variety of organic R functions (R,=,alkylthiols, phenylsulfonates, alkylphosphonates, dansyl, aminopropyl, fluoroalkyl, etc.). The resulting nanomaterials are thoroughly characterized by a variety of techniques. The use of a synergetic combination of achiral molecules as co-directing structuring agents, a surfactant, and an organofunctional silica precursor R-Si(OR)3 allows, via carefully tuning of the main synthesis parameters and processing conditions, to control the shape, which is the anisotropic factor, of the hybrid nanofibers. The functionalization of the hybrid materials with fluorescent molecules (dansyl) and gold nanoparticles opens possibilities for sensor and catalytic applications, respectively. Moreover, these hybrid nanofibers can be easily transferred in organic solvents or in a "green" solvent such as water to make stable colloidal dispersions. This tunable functionality of nanofibers also allows their transferability into a variety of polymeric hosts (PVDF, PVBu, and PVP) allowing the formation of functional homogeneous nanocomposite hybrid membranes. [source] A New Carbazole-Constructed Hyperbranched Polymer: Convenient One-Pot Synthesis, Hole-Transporting Ability, and Field-Effect Transistor PropertiesADVANCED FUNCTIONAL MATERIALS, Issue 16 2009Zhong'an Li Abstract A new hyperbranched polymer (HB-car), constructed fully by carbazole moieties, is successfully synthesized through a one-pot Suzuki coupling reaction. The resultant polymer is well-characterized, and its hole-transporting ability is studied carefully. The device, in which HB-car is utilized as a hole-transporting layer and tris-(8-hydroxyquinoline) aluminum as an electron-emitting layer as well as electron-transporting layer, gives a much higher efficiency (3.05,cd A,1), than that of a poly(N -vinylcarbazole) based device (2.19,cd A,1) under similar experimental conditions. The remarkable performance is attributed to its low energy barrier and enhanced hole-drifting ability in the HB-car based device. In addition, for the first time, a field-effect transistor (FET) based on the hyperbranched polymer is fabricated, and the organic FET device shows that HB-car is a typical p -type FET material with a saturation mobility of 1,×,10,5,cm2 V,1 s,1, a threshold voltage of ,47.1,V, and an on-to-off current ratio of 103. [source] Supercritical-Fluid-Assisted One-Pot Synthesis of Biocompatible Core(, -Fe2O3)/Shell(SiO2) Nanoparticles as High Relaxivity T2 -Contrast Agents for Magnetic Resonance ImagingADVANCED FUNCTIONAL MATERIALS, Issue 14 2009Elena Taboada Abstract Monodisperse iron oxide/microporous silica core/shell composite nanoparticles, core(, -Fe2O3)/shell(SiO2), with a diameter of approximately 100,nm and a high magnetization are synthesized by combining sol,gel chemistry and supercritical fluid technology. This one-step processing method, which is easily scalable, allows quick fabrication of materials with controlled properties and in high yield. The particles have a specific magnetic moment (per kg of iron) comparable to that of the bulk maghemite and show superparamagnetic behavior at room temperature. The nanocomposites are proven to be useful as T2 MRI imaging agent. They also have potential to be used in NMR proximity sensing, theranostic drug delivery, and bioseparation. [source] Uniform Magnetic Chains of Hollow Cobalt Mesospheres from One-Pot Synthesis and Their Assembly in Solution,ADVANCED FUNCTIONAL MATERIALS, Issue 3 2007L. Guo Abstract Magnetic chains up to 10,,m in length formed of hollow cobalt mesospheres (480,850,nm) with a 60,nm thick shell are synthesized by a new soft-assembly protocol. The obtained chains show a saturation magnetization of 37.5,emu,g,1, a remnant magnetization of 1.55,emu,g,1, and a coercivity of ca.,66,Oe at 300,K. A possible mechanism for the formation of the chainlike hollow structures is proposed. [source] One-Pot Synthesis of 5-Substituted 1H -Tetrazoles from Aryl Bromides with Potassium Hexakis(cyano- ,C)ferrate(4,) (K4[Fe(CN)6]) as Cyanide SourceHELVETICA CHIMICA ACTA, Issue 1 2009Yizhong Zhu Abstract A one-pot procedure for the synthesis of 5-substituted 1H -tetrazoles through the three-component reaction between an aryl bromide, potassium hexakis(cyano- ,C)ferrate(4,) (K4[Fe(CN)6]) and NaN3 catalyzed by [Pd(OAc)2] and ZnBr2 in the presence of 1,4-diazabicyclo[2.2.2]octane (dabco) was developed. Furthermore, the reaction occurred under nonacidic conditions and involved a nontoxic cyanide source, making this method a quite attractive one. [source] One-Pot Synthesis of Tetraalkyl Benzene-1,2,3,5-tetracarboxylates from a Four-Component Reaction of Alkyl Propiolates and Alkyl 2-Nitroethanoates Promoted by Ph3PHELVETICA CHIMICA ACTA, Issue 12 2006Issa Yavari Abstract Alkyl 2-nitroethanoates react with alkyl propiolates in the presence of triphenylphosphine (Ph3P) in a mechanistically unprecedented reaction to afford tetraalkyl benzene-1,2,3,5-tetracarboxylates in moderate yields (36,42%). [source] One-Pot Synthesis of Catalytically Stable and Active Nanoreactors: Encapsulation of Size-Controlled Nanoparticles within a Hierarchically Macroporous Core@Ordered Mesoporous Shell SystemADVANCED MATERIALS, Issue 13 2009Xiao-Yu Yang Size-controlled, catalytically active nanoparticles are successfully encapsulated in a one-pot synthesis to form novel hierarchical macroporous core@mesoporous shell structures, where macroporous cores are connected by uniform and ordered mesoporous channels. Most importantly, the encapsulated nanoparticles can be used as "nanoreactors", with high activities and excellent long-term recycling stability. [source] Facile Synthesis of Fe2O3 Nanocrystals without Fe(CO)5 Precursor and One-Pot Synthesis of Highly Fluorescent Fe2O3,CdSe NanocompositesADVANCED MATERIALS, Issue 8 2009Chung Yen Ang ,-Fe2O3 nanocrystals are synthesized in high yield (2,g) without a hazardous precursor and with a less-expensive oxidant in a one-pot synthesis (see figure). Bifunctional magnetic quantum-dot (, -Fe2O3,CdSe) nanocomposites are also synthesized in high yield, with a photoluminescence quantum yield of up to 42%. [source] One-Pot Synthesis of Quinoline Derivatives Directly from Terminal Alkynes via Sequential Ruthenium(II) and Acid CatalysisADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 11-12 2010Min Zhang Abstract A convenient one-pot synthesis of 2,3-disubstituted, 2,3,6-trisubstituted, and 2,3,6,7-tetrasubstituted quinoline analogues from terminal alkynes via sequential ruthenium(II) and para -toluenesulfonic acid (p -TSA) co-catalyzed reactions is described. The catalytic process is shown to take place first via intermediate formation of an allyl ketone and then addition of an aniline derivative to the allyl ketone. The p -TSA is a catalyst for both allyl ketone and quinoline synthetic steps. The method allowed us to synthesize a wide range of quinoline derivatives and introduce different substituents by employing various simple starting materials. The reaction allows the synthesis of halogen-containing products. [source] Highly Efficient One-Pot Synthesis of 2-Substituted Quinazolines and 4H -Benzo[d][1,3]oxazines via Cross Dehydrogenative Coupling using Sodium HypochloriteADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 2-3 2010C. Uma Maheswari Abstract This communication describes a catalyst-free synthesis of 2-substituted quinazolines and 4H -benzo[d][1,3]oxazines using commericially available sodium hypochlorite as oxidant. Operational simplicity, mild reaction conditions and the ability to construct structurally diverse 2-quinazolines and 2-substituted 4H -benzo[d][1,3]oxazines by this method render it to be a practical alternative for the synthesis of these heterocycles. [source] Copper-Catalyzed One-Pot Synthesis of Substituted BenzimidazolesADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 2-3 2010Hongwei Jin Abstract A copper-catalyzed one-pot synthesis of functionalized benzimidazoles has been developed. The procedure combines the copper-catalyzed three-component cascade reaction of sulfonyl azides, alkynes and 2-bromoaniline and the copper-catalyzed intramolecular N -arylation of sulfonamides in one sequence, which afforded the products in moderate to good yields. [source] One-Pot Synthesis of Carbamoyl Azides Directly from Primary Alcohols and Oxidation of Secondary Alcohols to Ketones Using Iodobenzene Dichloride in Combination with Sodium AzideADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 14-15 2009Xiao-Qiang Li Abstract An effective synthesis of carbamoyl azides directly from primary alcohols using iodobenzene dichloride in combination with sodium azide has been developed. Moreover, the same regent combination was also efficient for the oxidation of secondary alcohols to the corresponding ketones. [source] N,N,N,,N, -Tetramethylchloroformamidinium Chloride-Mediated Cyclizations of ,-Oxo Amides: Facile and Divergent One-Pot Synthesis of Substituted 2H -Pyrans, 4H -Pyrans and Pyridin-2(1H)-onesADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 13 2009Yan Wang Abstract An efficient and divergent one-pot synthesis of substituted 2H -pyrans, 4H -pyrans and pyridin-2(1H)-ones from ,-oxo amides based on the selection of the reaction conditions is reported. Mediated by N,N,N,,N, -tetramethylchloroformamidinium chloride, ,-oxo amides underwent intermolecular cyclizations in the presence of triethylamine at room temperature to give substituted 2H -pyrans in high yields, which could be converted into substituted 4H -pyrans in the presence of sodium hydroxide in ethanol at room temperature, or into substituted pyridin-2(1,H)-ones under reflux. [source] Copper-Catalyzed One-Pot Synthesis of 2-Alkylidene-1,2,3,4- tetrahydropyrimidinesADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 11-12 2009Wei Lu Abstract A one-pot synthesis of N -sulfonyl-2-alkylidene-1,2,3,4-tetrahydropyrimidines via a highly selective and copper-catalyzed multicomponent reaction of sulfonyl azides, terminal alkynes and ,,,-unsaturated imines has been developed. The ,,,-unsaturated imine substrates could be generated from amines and ,,,-unsaturated aldehydes in a one-pot process. The procedure is concise, general and efficient. [source] Promiscuous Zinc-Dependent Acylase-Mediated One-Pot Synthesis of Monosaccharide-Containing Pyrimidine Derivatives in Organic MediumADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 11-12 2009Qi Wu Abstract A facile one-pot synthesis route to monosaccharide-containing pyrimidine derivatives was developed by combining the two types of catalytic activities of one enzyme in an organic medium, i.e., the Michael addition/acylation activities of zinc-dependent D -aminoacylase (DA) from Escherichia coli. First, the stepwise approach was investigated. DA showed higher activity towards the Michael addition than acylation in this reaction system. The enzymatic Michael additions of pyrimidines to vinyl acrylate proceeded very rapidly and the initial reaction rates for the Michael addition of pyrimidines to vinyl acrylate were 7.2,16.5,mM,min,1. The catalytic specificity of aminoacylases toward Michael addition was demonstrated by the combination of different control experiments. Then, the two steps could be performed in one pot and a single aminoacylase catalyzed one-pot biotransformation was constructed. Using this strategy, a series of saccharide-pyrimidine complexes with potentially biological and pharmacological applications was prepared efficiently. This high Michael addition activity of zinc-dependent aminoacylases and the novel single aminoacylase-catalyzed one-pot synthesis combining two catalytic activities in vitro is of practical significance in expanding the application of enzymes and in the evolution of new biocatalysts. [source] | ||||||||||||||||||||||||||||