Solid—phase Synthesis of α—Haloaldehydes form Polymer—supported 4—（Phenylseleno）morpholine

Polystyrene-supported 4-(phenylseleno)morpholine was synthesized and could be used as an efficient α-selenenylating agent for saturated aldehydes.α-Haloaldehydes were prepared by reaction of polystyrene-supported α-selenoaldehydes with bromine or sulfuryl chloride in good yield and high purity.     

Study on Bicoordination Chiral Inducement Catalysis of （R）-4-Thiazolidinecarboxylic Acid

The bicoordination chiral inducement catalysis of (R)-4-thiazolidinecarboxylic acid in the enantioselective borane reduction of prochiral ketones has been studied. The fact that the absolute configuration of the main product can be changed by simply using different operation methods was firstly verified. And the reason of bicoordination chiral inducement was discussed.     

Crystal Structure and DFT Studies of a Triazole Derivative： 4- （ 2-Hydrobenzylideneamino ） -3- （ 1,2,4-triazol-4-ylmethyl） 1H-1, 2,4-triazole-5 （4H） -thione

A novel triazole derivative 4-(2-hydrobenzylideneamino)-3-(1,2,4-triazol-4-ylmethyl)-1H-1,2,4-triazole-5(4H)-thione(1) was synthesized and characterized using elemental analysis, FTIR, and 1H NMR, and its crystal structure was determined via X-ray single crystal diffraction analysis. Crystal data: monoclinic, P2(1)/c, a=0.83335(9) nm, b=1.49777(16) nm, c=1.14724(12) nm, β =107.990(2)°, D=1.470 Mg/m3, and Z=4. The geometries and the vibrational frequencies were determined using the density functional theory(DFT) method at the B3LYP/ 6-31G level. To demonstrate the accuracy of the reaction route of compound 1, one of the important intermediates was also tested using the same method. The structural parameters of the two compounds calculated using the DFT study are close to those of the crystals, and the harmonic vibrations of the two compounds computed via the DFT method are in good agreement with those in the observed IR spectral data. The thermodynamic properties of the title compound were calculated, and the compound shows a good structural stability at normal temperature. The test results of biological activities show that it has a certain bactericidal ability.     

Synthesis and Conformational Properties of Bis（calix [4] arene）

The bis(calix [4] arene)3 was synthesized in moderate yield by the reaction of p-tert-butylcalix [4] arene (1) with 1,4-bis(chloromethyl) benzene (2). The conformation of all alkylated product 4 was investigated by the variable-temperature ^1H-NMR.     

Synthesis and Structure of a Novel Copper（Ⅱ） Dinuclear Complex with 4,4′-Dipyridyl as the Bridge

With N,N′-bis(benzimidazol-2-methyl)amine as the ligand,a novel Cu(Ⅱ) dinuclear complex was synthesized as a mimetic compound of superoxide dismutase(SOD).The complex was characterized with element analysis,UV and IR spectra.The crystal structure was determined by using X-ray diffraction analysis.the crystal structure shows that Cu(Ⅱ) and its coordinated atoms construct distorted octahedron configuration with oxygen atome of (ClO4-)s in the axial directions.The coordinated cations are linked by (ClO4-)s to form nonplanar sheets.All sheets are linked together into three-dimensional network by the intermolecular hydrogen bonds.The result of the activity assay indicates that the complex does have certain biological activity.     

Reaction of Ketene Dithioacetals with Pyrazolylcarbohydrazide： Synthesis and Biological Activities of Ethyl 5-Amino-1-（5＇-methyl-1 ＇-t-butyl-4＇-pyrazolyl）carbonyl-3-methylthio-1 H-pyrazole-4-carboxylate

The title compound, C16H23N5O3S, ethyl 5-amino-1-(5‘-methyl-1‘-t-butyl-4‘-pyrazolyl)carbonyl-3-methylthio-1H-pyrazole-4-carboxylate (5) has been synthesized by the treatment of ethyl 2-cyano-3,3-dimethylthioacrylate with 1-t-butyl-5-methyl-4-hydrazinocarbonylpyrazole (4) in refluxed ethanol. The possible mechanism of the above reaction was also discussed. The results of biological test show that the title compound has fungicidal and plant growth regulation activities.     

Synthesis of （2R,4R）—2—N—tert—Butyloxycarbonyl Amino—4,5—epoxido—valeric Acid Methyl Ester

The stereoselective synthesis of (2R,4R)-2-N-tert-butyloxycarbonyl amino-4,5-epoxido-valeric acid methyl ester 8,which is the key intermediate for the synthesis of (2′S,2R)-3-trans-nitrocyclopropyl-alanine,was first accomplished.     

Synthesis of Novel Nucleoside Analog （3R）-2,3-Dideoxy-3-（N-hydroxy-N-methylamino）-L-arabinofuranosyl Uracil

The synthesis of novel nucleoside analog (3R)-2,3-dideoxy-3-(N-hydroxy-N-methylamino)-L-arabinofuranosyl uracil was studied. A twelve-step synthetic route, started from L-ascorbic acid, was designed, and the final product was obtained in 20.8% yield.     

The Selective Reduction of 4-Propylthio-2-nitroaniline with CO Using Ru3（CO）12／PEDPA Complex as Catalyst

The Ru3(CO)12/PEDPA complex was firstly applied in the CO selective reduction of 4-propylthio-2-nitroaniline.The effects of reaction temperature,the pressure of CO and concentration of catalyst on the reduction were investigated.Under the optimum conditions of T=140℃, Pco=5.0MPa and substrate/catalyst=300(molar ratio),the conversion and selectivity were 70% and 98%,respectively.After simple phase separation,the catalyst could be recycled.     

Synthesis and Bioactivity of Novel Aminomethyl-2-（1, 2,4-triazol）-4, 4-dimethyl-3-pentanone （ol）

3, 3-Dimethyl-1-(1,2,4-triazol)-2-butanone was treated with aqueous formaldehyde to give an additional product, and subsequent elimination by acetic anhydride yielded 4,4-dimethyl-2-(1,2,4-triazol)-1-penten-3-one. Further addition with substituted amines provideda series of (1,2,4-triazol)-4,4-dimethyl-3-pentanone, which were then reduced by KBH4 to obtaina series of (1,2,4-triazol)-4,4-dimethyl-3-pentanol. Their structures were confirmed by ^1HNMR and elemental analysis. The results of bioassay showed that the title products possess good fungicidal activities.     

Reactions of Polymer‐Supported α‐Selenoaldehydes with Grignard Regents. A Facile Solid‐Phase Stereoselective Synthesis of (E)‐1,2‐Disubstituted Ethenes

Polymer‐supported α‐selenoaldehydes easily obtained by reaction of polymer‐supported 4‐(phenylseleno)morpholine with aldehydes react with Grignard reagents to form polymer‐supported β‐hydroxyalkyl selenides, which were treated with thionyl chloride/triethylamine leading to (E)‐1,2‐disubstituted ethenes in good yields.     

Solid-phase Synthesis of-Haloaldehydes from Polymer-supported 4-(Phenylseleno)morpholine

Polymer-supported reagents for organic synthesis are enjoying a renewed popularity with the emergence of combinatorial chemistry in recent years1. 4-(Arylseleno)morpholines formed in situ are useful -seleno-introducing reagents for saturated aldehydes2. -Sele- noaldehydes, as a frequently used intermediates, can be converted into -haloaldehydes by halogenating reaction3. However, organic selenium reagents always have a foul smell and are quite toxic, which is often problematic in organic sy…     

Stereoselective Synthesis of （Z）-5-（Trideca-4-enyl）resorcinol and Gibbilimbols A-D

(Z)-5-(Trideca-4-enyl)resorcinol (1) and gibbilimbols A-D(2-5) were synthesized in 47%-60% yields over 6 steps from commercially available starting materials. The Wittig reaction of various alkyl phosphonium bromides with appropriate aldehydes in the presence of potassium tert-butoxide (t-BuOK) in anhydrous THF solution at room temperature served as the key step, and the result showed that only (Z)-configuration olefins were formed by this procedure. The synthesis of the (Z)-5-(trideca-4-enyl)resorcinol (1) was reported for the first time.     

1,3‐Dihydro‐1‐hydroxy‐3‐morpholin‐4‐yl‐2,1‐benzoxaborole: product of the reaction of o‐formylphenylboronic acid with morpholine

o‐Formylphenylboronic acid reacts with morpholine to form 1,3‐dihydro‐1‐hydroxy‐3‐morpholin‐4‐yl‐2,1‐benzoxaborole. The typical hydrogen‐bonded dimer motif with a planar benzoxaborole fragment has been obtained in the solid state. Copyright © 2005 John Wiley & Sons, Ltd.     

Construction of a three-dimensional network with open channels via Ag–Ag and π–π interactions between nanoscale sized molecular chains

The reaction of Ag₂O with pybz (pybz=4-(4-pyridyl)benzoate) gave the monomer compound [Ag(pycz)(H₂O)], 1. Using 4,4′-bipyridyl (bpy) as a spacer to increase the length of the monomer resulted in the nanosized molecular chain compound [Ag₂(pybz)₂(bpy)], 2. In 1, two monomers [Ag(pycz)(H₂O)] are combined together through Agπ, ππ and Ag(CC) interactions to form a dimer, with the distances of 3.34, 3.56 and 3.18 Å, respectively. In 2, the [Ag₂(pybz)₂(bpy)] units are held together via ππ (3.4–3.5 Å) interactions resulting in a 3D network with 1D open channels.     

Reaction of 2-chloro-3-(4-N,N-dimethylaminoanilino)-1,4-naphthoquinone with cyclic amines (piperidine,morpholine, and pyrrolidine)

It was shown that the reaction of 2-chloro-3-(4-N,N-dimethylaminoanilino)-1,4-naphthoquinone with piperidine in the absence of a solvent gives not only a product of replacement of the chlorine atom by a piperidino group, 3-(4-N,N-dimethylaminoanilino)-2-piperidino-1,4-naphthoquinone, but also 2-(4-N,N-dimethylaminoanilino)-1,4-naphthoquinone and 2-(4-N,N-dimethylaminoanilino-2-piperidino)-1,4-naphthoquinone. The latter compounds are the only reaction products formed in dimethyl sulfoxide. The reaction with morpholine occurs in a similar way, whereas that with pyrrolidine gives only a product of replacement of the chlorine atom by hydrogen.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2451–2454, December, 1995.     

New domino‐reaction for the synthesis of N4‐(5‐aryl‐1,3‐oxathiol‐2‐yliden)‐2‐phenylquinazolin‐4‐amines and 4‐[4‐aryl‐5‐(2‐phenylquinazolin‐4‐yl)‐1,3‐thiazol‐2‐yl]morpholine

The model morpholine‐1‐carbothioic acid (2‐phenyl‐3H‐quinazolin‐4‐ylidene) amide (1) reacts with phenacyl bromides to afford N⁴‐(5‐aryl‐1,3‐oxathiol‐2‐yliden)‐2‐phenylquinazolin‐4‐amines (4) or N⁴‐(4,5‐diphenyl‐1,3‐oxathiol‐2‐yliden)‐2‐phenyl‐4‐aminoquinazoline ( 5 ) by a thermodynamically controlled reversible reaction favoring the enolate intermediate, while the 4‐[4‐aryl‐5‐(2‐phenylquinazolin‐4‐yl)‐1,3‐thiazol‐2‐yl]morpholine ( 8 ) was produced by a kinetically controlled reaction favoring the C‐anion intermediate. ¹H nmr, ¹³C nmr, ir, mass spectroscopy and x‐ray identified compounds ( 4 ), ( 5 ) and ( 8 ).     

Novelties of cyanide displacement reaction in ibuprofen amide process by phase transfer catalysis: Solid–liquid versus solid–liquid (omega)–liquid systems

This work deals with the phase transfer catalysed cyanide displacement reaction on 1-(4-isobutyl phenyl) ethyl chloride to synthesize 2-(4-isobutyl phenyl) propionitrile, which is an intermediate for the synthesis of ibuprofen analogs, belonging to a class of NSAID (nonsteroidal anti-inflammatory drugs). The reaction was studied using solid–liquid phase transfer catalysis (S-L PTC) with trace quantities of water, forming the so-called omega phase at 90 °C. The rates of reaction and selectivity to the product are enhanced in the S-L(org.)-L (ω) PTC in comparison with S-L PTC, which in turn is superior to L-L PTC; the latter suffers from the disadvantage of side reactions in the aqueous phase. In the current work, the effects of various parameters such as catalyst structure, catalyst loading, substrate loading and temperature were studied on the conversion and rates of reaction of 1-(4-isobutyl phenyl) ethyl chloride with solid sodium cyanide under S-L and S-L(ω)-L PTC at 90 °C with toluene as the organic solvent. Tetrabutylammonium bromide (TBAB) was found to be the best catalyst. The role of omega liquid phase in intensification of the S-L PTC was theoretically and experimentally investigated. The kinetic constants have been determined and the apparent activation energy is found as 4.2 kcal/mol, which suggests that the reaction is quite fast, which is likely to bring in mass transfer effects.     

Synthesis of Three‐, Five‐, and Six‐Membered Heterocycles Derived from New β‐Amino‐α‐(trifluoromethyl) Alcohols

Nucleophilic trifluoromethylation of α‐imino ketones 2 , derived from arylglyoxal, with Ruppert–Prakash reagent (CF₃SiMe₃) offers a convenient access to the corresponding O‐silylated β‐imino‐α‐(trifluoromethyl) alcohols. In a ‘one‐pot’ procedure, by treatment with NaBH₄, these products smoothly undergo reduction and desilylation yielding the expected β‐amino‐α‐(trifluoromethyl) alcohols 4 . The latter were used as starting materials for the synthesis of diverse trifluoromethylated heterocycles, including aziridines 5 , 1,3‐oxazolidines 8 , 1,3‐oxazolidin‐2‐ones 9 , 1,3,2‐oxazaphospholidine 2‐oxides 10 , 1,2,3‐oxathiazolidine 2‐oxides 11 , and morpholine‐2,3‐diones 12 . An optically active 5‐(trifluoromethyl)‐substituted 1,3‐oxazolidin‐2‐one 9g was also obtained.