Consecutive Reaction of Bis[2,2,2-trifluoroethyl]phosphite.Onepot Synthesis of Substituted 3-Cyano-β,γ-unsaturated Nitriles with Exclusive or Predominant E-Selectivity

The consecutive reaction of bis [2,2,2-trifluoroethyl ] phosphite and its application to the one-pot synthesis of 3-cyano-β,γ-un-saturated nitriles with exclusive or predominant E-selectivity (E:Z = 100-85:0-15) and excellent yields (94%-99%) are described.

Optimization of technological conditions for one-pot synthesis of (S)-α-cyano-3-phenoxybenzyl acetate in organic media

Optically active form of α-cyano-3-phenoxybenzyl (CPB) alcohol, building block of pyrethroid insecticides, was synthesized as its acetate by the combination of anion-exchange resin (D301)-catalyzed transcyanation between m-phenoxybenzaldehyde (m-PBA) and acetone cyanohydrin (AC), and lipase (from Alcaligenes sp.)-catalyzed enantioselective transesterification of the resulting cyanohydrin with vinyl acetate. Through optimizing technological conditions, the catalyzing efficiency was improved considerably compared to methods previously reported. Concentrations of CPB acetate were determined by gas chromatograph. The enantio excess (e.e.) values of CPB acetate were measured by NMR (nuclear magnetic resonance) method. Effects of solvents and temperatures on this reaction were studied. Cyclohexane was shown to be the best solvent among the three tested solvents. 55 °C was the optimal temperature for higher degree of conversion. External diffusion limitation was excluded by raising the rotational speed to 220 r/min. However, internal diffusion could not be ignored, since the catalyst (lipase) was an immobilized enzyme and its particle dimension was not made small enough. The reaction rate was substantially accelerated when the reactant (m-PBA) concentration was as high as 249 mmol/L, but decreased when the initial concentration of m-PBA reached to 277 mmol/L. It was also found that the catalyzing capability of recovered lipase was high enough to use several batches. Study of the mole ratio of AC to m-PBA showed that 2:1 was the best choice. The strategy of adding base catalyst D301 was found to be an important factor in improving the degree of conversion of the reaction from 20% to 80%. The highest degree of conversion of the reaction has reached up to 80%.

Microwave promoted one-pot synthesis of 3-(2′-amino-3′-cyano-4′-arylpyrid-6′-yl)coumarins

A facile procedure for the synthesis of 3-（2′-amino-3′-cyano-4′-arylpyrid-6′-yl） coumarins are being reported starting from 3- acetylcoumarin, aromatic aldehydes and malononitrile. The reactions were carried out on microwave irradiation in good yield with short time and easy work-up. The structures of all the compounds have been confirmed on the basis of their analytical, IR, ^1H NMR, and mass spectral data.

A novel synthesis of 5-aryl-3-cyano-2-pyridones by using vinamidinium salts

A variety of vinamidinium salts were condensated with cyanoacetamide in refluxing methanol that contained sodium methoxide to produce 5-aryl-3-cyano-2-pyridones in good yield. Simple experimental conditions were used to prepare ten different 5-aryl-3- cyano-2-pyridones, four of which are new compounds.C 2009 Song Li. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

Synthesis of 1,2:4,5-di-O-Isopropylidene-3-C-Cyano-β-D-ribo-hex-2-ulo Pyranose by Phase Transition Catalysis

Introduction The cyano branched carbohydrates are useful, versatil intermediaries for the synthesis of branched sugars having biological activity in nature. Owing to the good yield, mild reaction conditions and high stereospecificity, the phase transition catalysis(PTC)method has been widely used to the syntheses of C-

DMAP催化的17β-氰基-17α-羟基雄甾-4-烯-3-酮硅醚化反应研究

以4-二甲氨基吡啶(DMAP)为催化剂,氯甲基二甲基氯硅烷(CDCS)为硅醚化试剂,Et3N为缚酸剂,5℃反应2 h,对17β-氰基-17α-羟基雄甾-4-烯-3-酮(I)的17α-OH进行硅醚化保护,生成17β-氰基-17α-羟基雄甾-4-烯-3-酮-17-氯甲基二甲基硅醚(II)。研究水分、p H、DMAP用量及投料顺序对化合物(I)硅醚化反应的影响。在最佳反应条件下,化合物收率98.70%,纯度99.07%。

A cesium fluoride promoted efficient and rapid multicomponent synthesis of functionalized 2-amino-3-cyano-4H-pyran and spirooxindole derivatives

A rapid, one-pot and highly efficient protocol for the synthesis of pharmaceutically interesting functionalized 2-amino-3-cyano-4H-pyran and spirooxindole derivatives has been developed using commercially available Cs F as a catalyst in the reaction of malononitrile and aryl aldehydes or isatins with 1,3-cyclohexanediones. The major advantages of this methodology are excellent yield at ambient temperature, very short reaction time（5–10 min）, and use of an inexpensive catalyst.

Michael-Addition Reaction of Malononitrile with a,β-Unsaturated Cycloketones Catalyzed by KF/Al_2O_3

A series of KF/Al2O3 catalyzed Michael-addition reactions between malononitrile and a,b-unsaturated cycloke-tones in DMF solution were studied. At room temperature, 2-cyano-3-aryl-3-(1,2,3,4-tetrahydronaphthalen- 1-one-2-yl) propionitrile derivatives were synthesized by the reaction between 2-arylmethylidene-1,2,3,4-tetra-hydronaphthalen-1-one and malononitrile. However, if the temperature was increased to 80 ℃, 2-amino-3-cyano-4- aryl-4H-benzo[h]chromene derivatives were obtained in high yields. When the a,b-unsaturated ketones were re-placed by 2,6-biarylmethylidenecyclohexanone or 2,5-biarylmethylidenecyclopentanone, another series of 2-amino- 3-cyano-4H-pyran derivatives was isolated successfully. The structures of the products were confirmed by X-ray diffraction analysis.

An environmentally friendly synthesis of 1,4-dihydropyrano[2,3-c]pyrazole derivatives catalyzed by tungstate sulfuric acid

An efficient three-component synthesis of 6-amino-4-aryl-5-cyano-3-metriyl-1-phenyl-1,4-dihydropyrano[2,3-c]pyrazoles via a reaction between 3-methyl-1-phenyl-2-pyrazolin-5-one,aromatic aldehydes and malononitrile using tungstate sulfuric acid as a catalyst was described.Mild conditions,good to excellent yields,easily available catalyst and easy work-up are the key features of this method.

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-1H-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 5,6-Diarylpyridin-2（1H）-ones from Isoflavones

A simple method for the cyclocondensation of substituted isoflavones with cyanoacetamide in the presence of sodium hydroxide to give an array of 3-cyano-5,6-diarylpyridin-2（1H）-ones in good yields is reported.

A New Cyano-compound from Rhodiola kirilowii

Objective To study the chemical constituents of Rhodiola kirilowii.Methods The compounds were separated and purified by various chromatographic techniques and their structures were elucidated on the basis of physicochemical properties and spectroscopic methods.Results Five compounds were purified and their structures were identified as 4-(β-D-glucopyranosyloxy)-3-hydroxy-2-(hydroxymethyl)-butanenitrile(1),epicatechin(2), arbutin(3),rutin(4),andβ-D-glucose(5).Conclusion Compound 1 is a new cyano-compound and other compounds are isolated from the plant for the first time.

Quantitative structure-retention relationship for photosystem Ⅱ inhibitors in RP-HPLC

Using factor analysis (principle component) and multiple linear regression methods,4 solute-related structure parameters were selected from 10 structure parameters and the relationships between the retention properties (logk’) of 25 2-cyano-3-methylthio-3-substituted amino-acrylates and the 4 parameters were established.There is a good agreement between the observed k’ values and the predicted fe’ values.